diff --git a/.github/workflows/pylint.yml b/.github/workflows/pylint.yml
index a3d4e5a12..82ddac36f 100644
--- a/.github/workflows/pylint.yml
+++ b/.github/workflows/pylint.yml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.13"]
+        python-version: ["3.10", "3.13"]
     steps:
     - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
@@ -23,4 +23,4 @@ jobs:
         pip install pylint
     - name: Analysing the code with pylint
       run: |
-        pylint $(git ls-files '*.py') --generated-members json,ssl,datetime --disable C0114
+        pylint $(git ls-files '*.py') --generated-members json,ssl,datetime --disable C0114 --errors-only
diff --git a/.github/workflows/regression-test-docker-image.yml b/.github/workflows/regression-test-docker-image.yml
index 7e115fce5..5cf6db676 100644
--- a/.github/workflows/regression-test-docker-image.yml
+++ b/.github/workflows/regression-test-docker-image.yml
@@ -35,11 +35,12 @@ jobs:
       run: |
         version=$(docker run ${{ env.TEST_TAG }} python --version)
         echo "Python version: $version"
-        if [[ "$version" != "Python 3.13"* ]]; then
-          echo "Error: Default python version is not 3.13 based, was we unable to change default version?"
+        if [[ "$version" != "Python 3.10"* ]] && [[ "$version" != "Python 3.11"* ]] && [[ "$version" != "Python 3.12"* ]] && [[ "$version" != "Python 3.13"* ]]; then
+          echo "Error: Default python version is not one of the allowed versions (3.10, 3.11, 3.12, 3.13)"
           exit 1
         fi
     - name: Check if webperf_core help command works
+      if: always()
       run: |
         help=$(docker run ${{ env.TEST_TAG }} python default.py -h)
         echo "$help"
@@ -48,6 +49,7 @@ jobs:
           exit 1
         fi
     - name: Check if dependency tool works
+      if: always()
       run: |
         help=$(docker run ${{ env.TEST_TAG }} python default.py --dependency)
         echo "$help"
diff --git a/.github/workflows/verify_browsertime_har.py b/.github/workflows/verify_browsertime_har.py
index 85da9fbe0..5c2dd8f2b 100644
--- a/.github/workflows/verify_browsertime_har.py
+++ b/.github/workflows/verify_browsertime_har.py
@@ -149,14 +149,14 @@ def validate_entry(entry_index, entry, page_refs, full_validation):
         print(f'Error: log.entries[{entry_index}].pageref is missing in browsertime.har file')
         is_ok = False
     elif entry['pageref'] not in page_refs:
-        print(f'Error: log.entries[{entry_index}].pageref has wrong value, actual value: {entry['pageref']}')
+        print(f"Error: log.entries[{entry_index}].pageref has wrong value, actual value: {entry['pageref']}")
         is_ok = False
 
     if 'time' not in entry:
         print(f'Error: log.entries[{entry_index}].time is missing in browsertime.har file')
         is_ok = False
     elif not isinstance(entry['time'], float) and  not isinstance(entry['time'], int):
-        print(f'Error: log.entries[{entry_index}].time has wrong value, actual value: {entry['time']}')
+        print(f"Error: log.entries[{entry_index}].time has wrong value, actual value: {entry['time']}")
         is_ok = False
 
     return is_ok
@@ -171,7 +171,7 @@ def validate_entry_response(entry_index, entry, full_validation):
         print(f'Error: log.entries[{entry_index}].response.status is missing in browsertime.har file')
         is_ok = False
     elif not isinstance(entry['response']['status'], int):
-        print(f'Error: log.entries[{entry_index}].response.status has wrong value, actual value: {entry['response']['status']}')
+        print(f"Error: log.entries[{entry_index}].response.status has wrong value, actual value: {entry['response']['status']}")
         is_ok = False
     elif entry['response']['status'] not in (
             100, 101, 102, 103,
@@ -183,7 +183,7 @@ def validate_entry_response(entry_index, entry, full_validation):
             431, 451,
             500, 501, 502, 503, 504, 505, 506, 507, 508, 510, 511
             ):
-        print(f'Error: log.entries[{entry_index}].response.status has wrong value, actual value: {entry['response']['status']}')
+        print(f"Error: log.entries[{entry_index}].response.status has wrong value, actual value: {entry['response']['status']}")
         is_ok = False
 
     if 'content' not in entry['response']:
@@ -194,26 +194,26 @@ def validate_entry_response(entry_index, entry, full_validation):
             print(f'Error: log.entries[{entry_index}].response.content.mimeType is missing in browsertime.har file')
             is_ok = False
         elif entry['response']['content']['mimeType'] not in ('text/html', 'text/html;charset=utf-8', 'text/html;charset=UTF-8', 'text/css', 'image/png', 'image/webp', 'text/javascript', 'font/woff2'):
-            print(f'Error: log.entries[{entry_index}].response.content.mimeType has wrong value, actual value: {entry['response']['content']['mimeType']}')
+            print(f"Error: log.entries[{entry_index}].response.content.mimeType has wrong value, actual value: {entry['response']['content']['mimeType']}")
             is_ok = False
 
         if 'size' not in entry['response']['content']:
             print(f'Error: log.entries[{entry_index}].response.content.size is missing in browsertime.har file')
             is_ok = False
         elif not isinstance(entry['response']['content']['size'], int):
-            print(f'Error: log.entries[{entry_index}].response.content.size has wrong value, actual value: {entry['response']['content']['size']}')
+            print(f"Error: log.entries[{entry_index}].response.content.size has wrong value, actual value: {entry['response']['content']['size']}")
             is_ok = False
         elif entry['response']['content']['size'] < 1 and ('status' not in entry['response'] and entry['response']['status'] != 204):
-            print(f'Error: log.entries[{entry_index}].response.content.size has wrong value, actual value: {entry['response']['content']['size']}')
+            print(f"Error: log.entries[{entry_index}].response.content.size has wrong value, actual value: {entry['response']['content']['size']}")
             is_ok = False
 
         if full_validation and 'compression' in entry['response']['content'] and not isinstance(entry['response']['content']['compression'], int):
-            print(f'Error: log.entries[{entry_index}].response.content.compression has wrong value type, actual value type: {type(entry['response']['content']['compression'])}')
+            print(f"Error: log.entries[{entry_index}].response.content.compression has wrong value type, actual value type: {type(entry['response']['content']['compression'])}")
             is_ok = False
 
         if 'text' not in entry['response']['content']:
                 if 'mimeType' in entry['response']['content'] and entry['response']['content']['mimeType'] in ('text/html;charset=utf-8', 'text/css', 'text/javascript'):
-                    print(f'Error: log.entries[{entry_index}].response.content.text is missing in browsertime.har file {entry['response']['content']['mimeType']}')
+                    print(f"Error: log.entries[{entry_index}].response.content.text is missing in browsertime.har file {entry['response']['content']['mimeType']}")
                     is_ok = False
         elif 'status' in entry['response'] and entry['response']['status'] == 204:
             # ignore this
@@ -224,7 +224,7 @@ def validate_entry_response(entry_index, entry, full_validation):
             # We would prefer to be able to use Firefox for this but currently we have a workaround
             # in place to only use chrome for when we need to read content of text based files.
             if full_validation:
-                print(f'Error: log.entries[{entry_index}].response.content.text has wrong value, actual value: {entry['response']['content']['text']}, content-type: {entry['response']['content']['mimeType']}')
+                print(f"Error: log.entries[{entry_index}].response.content.text has wrong value, actual value: {entry['response']['content']['text']}, content-type: {entry['response']['content']['mimeType']}")
                 is_ok = False
 
     if 'httpVersion' not in entry['response']:
@@ -243,7 +243,7 @@ def validate_entry_response(entry_index, entry, full_validation):
         print(f'Error: log.entries[{entry_index}].response.statusText is missing in browsertime.har file')
         is_ok = False
     elif not isinstance(entry['response']['statusText'], str):
-        print(f'Error: log.entries[{entry_index}].response.statusText has wrong value, actual value: {entry['response']['statusText']}')
+        print(f"Error: log.entries[{entry_index}].response.statusText has wrong value, actual value: {entry['response']['statusText']}")
         is_ok = False
 
     if 'headersSize' not in entry['response']:
@@ -270,14 +270,14 @@ def validate_entry_response_headers(entry_index, entry):
                 print(f'Error: log.entries[{entry_index}].response.headers[{header_index}].name is missing in browsertime.har file')
                 is_ok = False
             elif re.match(r'[0-9a-z\-]+', header['name'], re.IGNORECASE) is None:
-                print(f'Error: log.entries[{entry_index}].response.headers[{header_index}].name has wrong name, actual value: {header['name']}')
+                print(f"Error: log.entries[{entry_index}].response.headers[{header_index}].name has wrong name, actual value: {header['name']}")
                 is_ok = False
 
             if 'value' not in header:
                 print(f'Error: log.entries[{entry_index}].response.headers[{header_index}].value is missing in browsertime.har file')
                 is_ok = False
             elif re.match(r'[0-9a-z\-\.\"]+', header['value'], re.IGNORECASE) is None:
-                print(f'Error: log.entries[{entry_index}].response.headers[{header_index}].value has wrong value, actual value: {header['value']}')
+                print(f"Error: log.entries[{entry_index}].response.headers[{header_index}].value has wrong value, actual value: {header['value']}")
                 is_ok = False
             header_index += 1
 
@@ -297,10 +297,10 @@ def validate_entry_request(entry_index, entry, full_validation):
             is_ok = False
         else:
             if entry_index == 0 and entry['request']['url'] != 'https://webperf.se/':
-                print(f'Error: log.entries[{entry_index}].request.url has wrong value, actual value: {entry['request']['url']}')
+                print(f"Error: log.entries[{entry_index}].request.url has wrong value, actual value: {entry['request']['url']}")
                 is_ok = False
             if not entry['request']['url'].startswith('http://') and not entry['request']['url'].startswith('https://'):
-                print(f'Error: log.entries[{entry_index}].request.url has wrong value, actual value: {entry['request']['url']}')
+                print(f"Error: log.entries[{entry_index}].request.url has wrong value, actual value: {entry['request']['url']}")
                 is_ok = False
 
         if not full_validation:
@@ -310,36 +310,36 @@ def validate_entry_request(entry_index, entry, full_validation):
             print(f'Error: log.entries[{entry_index}].request.method is missing in browsertime.har file')
             is_ok = False
         elif entry['request']['method'] not in ('GET','POST', 'HEAD', 'PUT', 'DELETE', 'CONNECT', 'OPTIONS', 'TRACE', 'PATCH'):
-            print(f'Error: log.entries[{entry_index}].request.method has wrong value, actual value: {entry['request']['method']}')
+            print(f"Error: log.entries[{entry_index}].request.method has wrong value, actual value: {entry['request']['method']}")
             is_ok = False
 
         if 'queryString' not in entry['request']:
             print(f'Error: log.entries[{entry_index}].request.queryString is missing in browsertime.har file')
             is_ok = False
         elif entry_index == 0 and entry['request']['queryString'] != []:
-            print(f'Error: log.entries[{entry_index}].request.queryString has wrong value, actual value: {entry['request']['queryString']}')
+            print(f"Error: log.entries[{entry_index}].request.queryString has wrong value, actual value: {entry['request']['queryString']}")
             is_ok = False
 
         if 'headersSize' not in entry['request']:
             print(f'Error: log.entries[{entry_index}].request.headersSize is missing in browsertime.har file')
             is_ok = False
         elif not isinstance(entry['request']['headersSize'], int):
-            print(f'Error: log.entries[{entry_index}].request.headersSize has wrong value, actual value: {entry['request']['headersSize']}')
+            print(f"Error: log.entries[{entry_index}].request.headersSize has wrong value, actual value: {entry['request']['headersSize']}")
             is_ok = False
         # NOTE: Not required by HAR specification 1.2
         # elif entry['request']['headersSize'] == -1:
-        #     print(f'Warning: log.entries[{entry_index}].request.headersSize has wrong value, actual value: {entry['request']['headersSize']}')
+        #     print(f"Warning: log.entries[{entry_index}].request.headersSize has wrong value, actual value: {entry['request']['headersSize']}")
         #     is_ok = False
 
         if 'bodySize' not in entry['request']:
             print(f'Error: log.entries[{entry_index}].request.bodySize is missing in browsertime.har file')
             is_ok = False
         elif not isinstance(entry['request']['bodySize'], int):
-            print(f'Error: log.entries[{entry_index}].request.bodySize has wrong value, actual value: {entry['request']['bodySize']}')
+            print(f"Error: log.entries[{entry_index}].request.bodySize has wrong value, actual value: {entry['request']['bodySize']}")
             is_ok = False
         # NOTE: Not required by HAR specification 1.2
         # elif entry['request']['bodySize'] != 0:
-        #     print(f'Error: log.entries[{entry_index}].request.bodySize has wrong value, actual value: {entry['request']['bodySize']}')
+        #     print(f"Error: log.entries[{entry_index}].request.bodySize has wrong value, actual value: {entry['request']['bodySize']}")
         #     is_ok = False
 
         if 'cookies' not in entry['request']:
@@ -350,7 +350,7 @@ def validate_entry_request(entry_index, entry, full_validation):
             print(f'Error: log.entries[{entry_index}].request.httpVersion is missing in browsertime.har file')
             is_ok = False
         elif entry['request']['httpVersion'] not in ('http/1.1', 'h2','h3'):
-            print(f'Error: log.entries[{entry_index}].request.httpVersion has wrong value, actual value: {entry['request']['httpVersion']}')
+            print(f"Error: log.entries[{entry_index}].request.httpVersion has wrong value, actual value: {entry['request']['httpVersion']}")
             is_ok = False
 
         is_ok = validate_entry_request_headers(entry_index, entry) and is_ok
@@ -369,14 +369,14 @@ def validate_entry_request_headers(entry_index, entry):
                 print(f'Error: log.entries[{entry_index}].request.headers[{header_index}].name is missing in browsertime.har file')
                 is_ok = False
             elif re.match(r'[\:0-9a-z\-]+', header['name'], re.IGNORECASE) is None:
-                print(f'Error: log.entries[{entry_index}].request.headers[{header_index}].name has wrong name, actual value: {header['name']}')
+                print(f"Error: log.entries[{entry_index}].request.headers[{header_index}].name has wrong name, actual value: {header['name']}")
                 is_ok = False
 
             if 'value' not in header:
                 print(f'Error: log.entries[{entry_index}].request.headers[{header_index}].value is missing in browsertime.har file')
                 is_ok = False
             elif re.match(r'[0-9a-z\-\.\"\?/\*]*', header['value'], re.IGNORECASE) is None:
-                print(f'Error: log.entries[{entry_index}].request.headers[{header_index}].value has wrong value, actual value: {header['value']}')
+                print(f"Error: log.entries[{entry_index}].request.headers[{header_index}].value has wrong value, actual value: {header['value']}")
                 is_ok = False
             header_index += 1
 
@@ -409,7 +409,7 @@ def validate_page(page_index, page, full_validation):
     is_ok = True
     page_ref = None
     if page['_url'] != 'https://webperf.se':
-        print(f'Error: log.pages[{page_index}]._url has wrong value, actual value: {page['_url']}')
+        print(f"Error: log.pages[{page_index}]._url has wrong value, actual value: {page['_url']}")
         is_ok = False
 
     if not full_validation:
@@ -419,7 +419,7 @@ def validate_page(page_index, page, full_validation):
         print(f'Error: log.pages[{page_index}].id is missing in browsertime.har file')
         is_ok = False
     elif f'page_{page_index +1 }' not in page['id']:
-        print(f'Error: log.pages[{page_index}].id has wrong value, actual value: {page['id']}')
+        print(f"Error: log.pages[{page_index}].id has wrong value, actual value: {page['id']}")
         is_ok = False
         page_ref = page['id']
     else:
@@ -444,21 +444,21 @@ def validate_page(page_index, page, full_validation):
             print(f'Error: log.pages[{page_index}].pageTimings.onContentLoad is missing in browsertime.har file')
             is_ok = False
         elif not isinstance(page['pageTimings']['onContentLoad'], float) and not isinstance(page['pageTimings']['onContentLoad'], int):
-            print(f'Error: log.pages[{page_index}].pageTimings.onContentLoad has wrong value, actual value: {page['pageTimings']['onContentLoad']}')
+            print(f"Error: log.pages[{page_index}].pageTimings.onContentLoad has wrong value, actual value: {page['pageTimings']['onContentLoad']}")
             is_ok = False
 
         if 'onLoad' not in page['pageTimings']:
             print(f'Error: log.pages[{page_index}].pageTimings.onLoad is missing in browsertime.har file')
             is_ok = False
         elif not isinstance(page['pageTimings']['onLoad'], float) and not isinstance(page['pageTimings']['onLoad'], int):
-            print(f'Error: log.pages[{page_index}].pageTimings.onLoad has wrong value, actual value: {page['pageTimings']['onLoad']}')
+            print(f"Error: log.pages[{page_index}].pageTimings.onLoad has wrong value, actual value: {page['pageTimings']['onLoad']}")
             is_ok = False
 
     if '_url' not in page:
         print(f'Error: log.pages[{page_index}]._url is missing in browsertime.har file')
         is_ok = False
     if page['_url'] != 'https://webperf.se':
-        print(f'Error: log.pages[{page_index}]._url has wrong value, actual value: {page['_url']}')
+        print(f"Error: log.pages[{page_index}]._url has wrong value, actual value: {page['_url']}")
         is_ok = False
 
     if '_meta' not in page:
@@ -476,14 +476,14 @@ def validate_browser(browsertime_har):
             print('Error: log.browser.name is missing in browsertime.har file')
             is_ok = False
         if browsertime_har['log']['browser']['name'] not in ('firefox', 'Chrome'):
-            print(f'Error: log.browser.name has wrong value, actual value: {browsertime_har['log']['browser']['name']}')
+            print(f"Error: log.browser.name has wrong value, actual value: {browsertime_har['log']['browser']['name']}")
             is_ok = False
 
         if 'version' not in browsertime_har['log']['browser']:
             print('Error: log.browser.version is missing in browsertime.har file')
             is_ok = False
         if re.match(r'[0-9\.]+', browsertime_har['log']['browser']['version'], re.IGNORECASE) is None:
-            print(f'Error: log.browser.name has wrong value, actual value: {browsertime_har['log']['browser']['version']}')
+            print(f"Error: log.browser.name has wrong value, actual value: {browsertime_har['log']['browser']['version']}")
             is_ok = False
     return is_ok
 
diff --git a/Dockerfile b/Dockerfile
index b3e27a2d8..5ea3259da 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM sitespeedio/sitespeed.io:36.1.0
+FROM sitespeedio/sitespeed.io:36.2.1
 
 USER root
 
@@ -24,23 +24,6 @@ RUN apt-get update &&\
     update-ca-certificates && \
     rm -rf /var/lib/apt/lists/*
 
-# NOTE: Python speed improvements from: https://tecadmin.net/how-to-install-python-3-12-on-ubuntu/
-RUN add-apt-repository ppa:deadsnakes/ppa -y
-
-RUN apt update
-
-RUN apt install -y python3.13 python3.13-venv
-
-RUN apt install -y python3-pip
-
-RUN update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.13 311
-
-RUN update-alternatives --config python3
-
-RUN wget https://bootstrap.pypa.io/get-pip.py
-
-RUN python3.13 get-pip.py
-
 RUN apt -y autoremove
 
 # Add user so we don't need --no-sandbox.
@@ -66,18 +49,18 @@ COPY pa11y-docker-config.json /usr/src/runner/pa11y.json
 
 RUN chown --recursive sitespeedio:sitespeedio /usr/src/runner
 
+RUN python3 -m pip install -r requirements.txt --break-system-packages && \
+    python3 -m pip install --upgrade pip --break-system-packages && \
+    python3 -m pip install --upgrade setuptools --break-system-packages && \
+    python3 -m pip install pyssim Pillow image --break-system-packages
+
 # Run everything after as non-privileged user.
 USER sitespeedio
 
 RUN npm install --omit=dev
 
-RUN python3.13 -m pip install -r requirements.txt --break-system-packages && \
-    python3.13 -m pip install --upgrade pip --break-system-packages && \
-    python3.13 -m pip install --upgrade setuptools --break-system-packages && \
-    python3.13 -m pip install pyssim Pillow image --break-system-packages
-
-RUN python3.13 default.py --setting tests.sitespeed.xvfb=true --save-setting settings.json
+RUN python3 default.py --setting tests.sitespeed.xvfb=true --save-setting settings.json
 
 ENTRYPOINT []
 
-CMD ["python3.13", "default.py -h"]
+CMD ["python3", "default.py -h"]
diff --git a/LICENSE b/LICENSE
index 7feab5d06..38d573cfc 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020 Webperf.se
+Copyright (c) 2020-2025 Webperf.se
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/helpers/test_helper.py b/helpers/test_helper.py
index f65151ed5..30afdfea0 100644
--- a/helpers/test_helper.py
+++ b/helpers/test_helper.py
@@ -161,9 +161,7 @@ def get_error_info(url, test_type, ex):
     result.extend(get_versions())
     result.extend(['###############################################',
         '\n# Information:',
-        f"\nDateTime: { \
-            datetime.now().strftime('%Y-%m-%d %H:%M:%S') \
-        }",
+        f"\nDateTime: {datetime.now().strftime('%Y-%m-%d %H:%M:%S')}",
         f'\nUrl: {url}',
         f'\nTest Type(s): {test_type}',
         '\n###############################################'
diff --git a/helpers/translation_helper.py b/helpers/translation_helper.py
index 78eb82d6e..c26da4232 100644
--- a/helpers/translation_helper.py
+++ b/helpers/translation_helper.py
@@ -80,7 +80,7 @@ def validate_po_file(locales_dir, locale_name, language_sub_directory, file, msg
         if not os.path.exists(file_mo):
             print(
                 (f'  Expected compiled translation file not found, '
-                  f'file: "{file.replace('.po', '.mo')}"'))
+                  f"file: \"{file.replace('.po', '.mo')}\""))
             return False
 
         clear_cache = True
@@ -304,10 +304,11 @@ def validate_msg_ids(available_languages, msg_ids):
         for msg in msg_list:
             msg_langs.append(msg['locale_name'])
         nof_langs = len(msg_langs)
+        tmp_str = '","'.join(msg_langs)
         if nof_langs < nof_languages:
-            print(f"  # msgid \"{msg_id}\" only in \"{'\",\"'.join(msg_langs)}\"")
+            print(f"  # msgid \"{msg_id}\" only in \"{tmp_str}\"")
         else:
-            print(f"  # msgid \"{msg_id}\" occur multiple times \"{'\",\"'.join(msg_langs)}\"")
+            print(f"  # msgid \"{msg_id}\" occur multiple times \"{tmp_str}\"")
 
     if len(msg_ids_with_missing_language) > 0:
         is_valid = False
@@ -477,7 +478,7 @@ def validate_locales(base_directory, msg_ids):
 
     if len(available_languages) > 0:
         print('')
-        print(f'  Available Languages: {', '.join(available_languages)}')
+        print(f"  Available Languages: {', '.join(available_languages)}")
     else:
         print('  No languages found')
 
@@ -523,9 +524,8 @@ def validate_locale(msg_ids, locales_dir,
             if msgfmt_path is not None:
                 print(
                             '  - Trying to generate .mo file so it matches .po file')
-                bash_command = (f"python {msgfmt_path} -o "
-                                        f"{os.path.join(lang_sub_directory,
-                                                        file.replace('.po', '.mo'))} "
+                bash_command = (f"python {msgfmt_path} -o ",
+                                        f"{os.path.join(lang_sub_directory, file.replace('.po', '.mo'))} ",
                                         f"{os.path.join(lang_sub_directory, file)}")
 
                 with subprocess.Popen(
diff --git a/package.json b/package.json
index f46dec6aa..16b762a3a 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,7 @@
     "@sitespeed.io/plugin": "1.0.0",
     "@sitespeed.io/plugin-lighthouse": "12.3.0",
     "pa11y": "8.0.0",
-    "sitespeed.io": "36.1.0",
+    "sitespeed.io": "36.2.1",
     "stylelint": "16.13.2",
     "vnu-jar": "23.4.11",
     "webperf-sitespeedio-plugin": "2025.1.4",
@@ -22,4 +22,4 @@
   "engines": {
     "node": "20.x"
   }
-}
\ No newline at end of file
+}
diff --git a/tests/frontend_quality_yellow_lab_tools.py b/tests/frontend_quality_yellow_lab_tools.py
index cf6a49c81..d2b867ae4 100644
--- a/tests/frontend_quality_yellow_lab_tools.py
+++ b/tests/frontend_quality_yellow_lab_tools.py
@@ -136,7 +136,7 @@ def add_category_ratings(global_translation, local_translation, result_dict):
         if 'label' not in rule['policy']:
             continue
 
-        rule_label = f'- {local_translation(rule['policy']['label'])}'
+        rule_label = f"- {local_translation(rule['policy']['label'])}"
 
         # only do stuff for rules we know how to place in category
         if rule_key in performance_keys:
diff --git a/tests/lint_base.py b/tests/lint_base.py
index 26b7d4f1a..a4c94f01f 100644
--- a/tests/lint_base.py
+++ b/tests/lint_base.py
@@ -57,7 +57,7 @@ def get_errors(test_type, params):
 
         if 'https://' not in url and 'http://' not in url:
             raise ValueError(
-                f'Tested url must start with \'https://\' or \'http://\': {url}')
+                f"Tested url must start with \'https://\' or \'http://\': {url}")
 
         file_path = get_cache_path_for_file(url, True)
         if is_html:
diff --git a/tests/performance_sitespeed_io.py b/tests/performance_sitespeed_io.py
index aecbf1301..26ea18793 100644
--- a/tests/performance_sitespeed_io.py
+++ b/tests/performance_sitespeed_io.py
@@ -203,7 +203,7 @@ def validate_on_mobile_using_validator(url, validator_config):
         '--speedIndex true '
         '--browsertime.videoParams.createFilmstrip false '
         '--browsertime.chrome.args ignore-certificate-errors '
-        f'-n {get_config('tests.sitespeed.iterations')} '
+        f"-n {get_config('tests.sitespeed.iterations')} "
         '--preScript chrome-custom.cjs '
         f'{url}'
         f'{browertime_plugin_options}'
@@ -242,16 +242,16 @@ def get_browsertime_plugin_options(validator_config):
         for header in validator_config['headers']:
             browertime_plugin_options += (
                 f' --browsertime.webperf.header0{index}'
-                f' {header['name'].replace(' ', '%20').replace('=', '%3D')}='
-                f'{header['value'].replace(' ', '%20').replace('=', '%3D')}')
+                f" {header['name'].replace(' ', '%20').replace('=', '%3D')}="
+                f"{header['value'].replace(' ', '%20').replace('=', '%3D')}")
             index += 1
     if 'htmls' in validator_config:
         index = 1
         for header in validator_config['htmls']:
             browertime_plugin_options += (
                 f' --browsertime.webperf.HTML0{index}'
-                f' {header['replace'].replace(' ', '%20').replace('=', '%3D')}='
-                f'{header['replaceWith'].replace(' ', '%20').replace('=', '%3D')}')
+                f" {header['replace'].replace(' ', '%20').replace('=', '%3D')}="
+                f"{header['replaceWith'].replace(' ', '%20').replace('=', '%3D')}")
             index += 1
     return browertime_plugin_options
 
@@ -278,7 +278,7 @@ def validate_on_desktop_using_validator(url, validator_config):
         '--speedIndex true '
         '--browsertime.videoParams.createFilmstrip false '
         '--browsertime.chrome.args ignore-certificate-errors '
-        f'-n {get_config('tests.sitespeed.iterations')} '
+        f"-n {get_config('tests.sitespeed.iterations')} "
         '--preScript chrome-custom.cjs '
         f'{url}'
         f'{browertime_plugin_options}'
@@ -312,7 +312,7 @@ def validate_on_desktop(url):
         '--speedIndex true '
         '--browsertime.videoParams.createFilmstrip false '
         '--browsertime.chrome.args ignore-certificate-errors '
-        f'-n {get_config('tests.sitespeed.iterations')} '
+        f"-n {get_config('tests.sitespeed.iterations')} "
         '--preScript chrome-custom.cjs '
         f'{url}'
         )
@@ -344,7 +344,7 @@ def validate_on_mobile(url):
         '--speedIndex true '
         '--browsertime.videoParams.createFilmstrip false '
         '--browsertime.chrome.args ignore-certificate-errors '
-        f'-n {get_config('tests.sitespeed.iterations')} '
+        f"-n {get_config('tests.sitespeed.iterations')} "
         '--preScript chrome-custom.cjs '
         f'{url}'
         )
diff --git a/tests/utils.py b/tests/utils.py
index 12633a25a..02b129753 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -394,7 +394,7 @@ def get_http_content(url, allow_redirects=False, use_text_instead_of_content=Tru
         headers = {'user-agent': get_config('useragent')}
         hostname = urlparse(url).hostname
         if hostname == 'api.github.com' and get_config('github.api.key') is not None:
-            headers['authorization'] = f'Bearer {get_config('github.api.key')}'
+            headers['authorization'] = f"Bearer {get_config('github.api.key')}"
         response = requests.get(url, allow_redirects=allow_redirects,
                          headers=headers, timeout=get_config('general.request.timeout')*2)
 
diff --git a/tests/w3c_base.py b/tests/w3c_base.py
index b39069f55..bd414c3c3 100644
--- a/tests/w3c_base.py
+++ b/tests/w3c_base.py
@@ -55,7 +55,7 @@ def get_errors(test_type, params):
 
         if 'https://' not in url and 'http://' not in url:
             raise ValueError(
-                f'Tested url must start with \'https://\' or \'http://\': {url}')
+                f"Tested url must start with \'https://\' or \'http://\': {url}")
 
         file_path = get_cache_path_for_file(url, True)
         if is_html: