Locale fix for ie

[adoroshk]

Summary

This PR introduces changes to getBrowserLocale method to accommodate the way IE navigator works with browser language.

Why the change is needed

It has been reported that if the browser language is set to a different language, it translates correctly in all browsers but IE. The issue was pointed out to be coming from current implementation of the browser language being obtained from the navigator languages properties, which for IE differs from the rest of the browsers. Following tests indicated in favor of that:

I changed the language in IE browser from English to German and console logged the navigator language properties. I observed following:

navigator.languages: undefined
navigator.language: undefined
navigator.userLanguage: "en-US"
navigator.browserLanguage: "en-US"
navigator.systemLanguage: "de-DE"

It means that for IE the only navigator property that reflects the current browser language is navigator.systemLanguage.
The current implementation of getBrowserLocale method does not use navigator.systemLanguage property, hence error in IE. It does work good for the rest of the browsers though, as they take the language from navigator languages array. I tested it by changing the language from English to German in Chrome, Firefox, Safari and Edge and received following console output:

navigator.languages: Array(1)['de']
navigator.language: 'de'
navigator.userLanguage: undefined
navigator.browserLanguage: undefined
navigator.systemLanguage: undefined

Testing

This change was tested using:

• WDIO
• Jest
• Visual testing (please attach a screenshot or recording)
• Other (please describe below)
• No tests are needed

Following testing have been done for Chrome, Firefox, Safari and Edge:

1. The language of these browsers have been changed to supported locale (German language), the console.log for getBrowserLocale method returning result was correctly set to 'de' or 'de-DE' (German):

2. The language has been changed to not supported locale (Ukrainian language), the console.log for getBrowserLocale method returning result was correctly set to fall-back locale 'en' (English).
3. The browser language was set to English, the console.log for getBrowserLocale method returning result was correctly set to 'en' (English).

Screenshots of navigator language props in IE, Edge, Chrome and Safari

A screenshot of navigator props in IE:

A screenshot of multiple languages with German being primary language logged for Edge:

A screenshot of German as an only language logged for Chrome:

A screenshot of Ukrainian as an only language in Safari:

Additional Details

This PR resolves:

UXPLATFORM-7942

[sdadn]

Is this PR up to date with main?

[adoroshk]

Is this PR up to date with main?

@sdadn I just updated it from main and added a snapshot update per change it terra-button