diff --git a/common/paths/pathparser.go b/common/paths/pathparser.go
index 40297735ced..65399819b69 100644
--- a/common/paths/pathparser.go
+++ b/common/paths/pathparser.go
@@ -25,9 +25,10 @@ import (
 	"github.com/gohugoio/hugo/identity"
 )
 
-var defaultPathParser PathParser = PathParser{
+var DefaultPathParser = &PathParser{
 	IsContentExt: func(ext string) bool {
-		return false
+		// TODO1
+		return ext == "md"
 	},
 }
 
@@ -44,9 +45,8 @@ type PathParser struct {
 }
 
 // Parse parses component c with path s into Path using the default path parser.
-// Only used in tests. TODO1
 func Parse(c, s string) *Path {
-	return defaultPathParser.Parse(c, s)
+	return DefaultPathParser.Parse(c, s)
 }
 
 // NormalizePathString returns a normalized path string using the very basic Hugo rules.
diff --git a/hugofs/files/classifier_test.go b/hugofs/files/classifier_test.go
index f2fad56ca0f..b1a92faadd7 100644
--- a/hugofs/files/classifier_test.go
+++ b/hugofs/files/classifier_test.go
@@ -14,22 +14,11 @@
 package files
 
 import (
-	"path/filepath"
 	"testing"
 
 	qt "github.com/frankban/quicktest"
 )
 
-func TestIsContentFile(t *testing.T) {
-	c := qt.New(t)
-
-	c.Assert(IsContentFile(filepath.FromSlash("my/file.md")), qt.Equals, true)
-	c.Assert(IsContentFile(filepath.FromSlash("my/file.ad")), qt.Equals, true)
-	c.Assert(IsContentFile(filepath.FromSlash("textfile.txt")), qt.Equals, false)
-	c.Assert(IsContentExt("md"), qt.Equals, true)
-	c.Assert(IsContentExt("json"), qt.Equals, false)
-}
-
 func TestComponentFolders(t *testing.T) {
 	c := qt.New(t)
 
diff --git a/hugofs/walk.go b/hugofs/walk.go
index 3bb2f49233a..252cf997067 100644
--- a/hugofs/walk.go
+++ b/hugofs/walk.go
@@ -73,6 +73,10 @@ func NewWalkway(cfg WalkwayConfig) *Walkway {
 		panic("fs must be set")
 	}
 
+	if cfg.PathParser == nil {
+		cfg.PathParser = paths.DefaultPathParser
+	}
+
 	logger := cfg.Logger
 	if logger == nil {
 		logger = loggers.NewDefault()
@@ -161,8 +165,7 @@ func (w *Walkway) walk(path string, info FileMetaInfo, dirEntries []FileMetaInfo
 
 		dirEntries = DirEntriesToFileMetaInfos(fis)
 		for _, fi := range dirEntries {
-			if fi.Meta().PathInfo == nil && w.cfg.PathParser != nil {
-				// TODO1
+			if fi.Meta().PathInfo == nil {
 				fi.Meta().PathInfo = w.cfg.PathParser.Parse("", filepath.Join(pathRel, fi.Name()))
 			}
 		}
diff --git a/hugolib/content_map.go b/hugolib/content_map.go
index f89547ee8bf..fd387d0a172 100644
--- a/hugolib/content_map.go
+++ b/hugolib/content_map.go
@@ -164,7 +164,7 @@ func (cfg contentMapConfig) getTaxonomyConfig(s string) (v viewName) {
 	return
 }
 
-func (m *pageMap) AddFi(fi hugofs.FileMetaInfo, whatChanged *whatChanged) (pageCount uint64, resourceCount uint64, addErr error) {
+func (m *pageMap) AddFi(fi hugofs.FileMetaInfo, buildConfig *BuildCfg) (pageCount uint64, resourceCount uint64, addErr error) {
 	if fi.IsDir() {
 		return
 	}
@@ -227,147 +227,14 @@ func (m *pageMap) AddFi(fi hugofs.FileMetaInfo, whatChanged *whatChanged) (pageC
 			return
 		}
 	case paths.PathTypeContentData:
-		m.s.Log.Trace(logg.StringFunc(
-			func() string {
-				return fmt.Sprintf("insert pages from data file: %q", fi.Meta().Filename)
-			},
-		))
-
-		if !files.IsGoTmplExt(pi.Ext()) {
-			addErr = fmt.Errorf("unsupported data file extension %q", pi.Ext())
-			return
-		}
-		// TODO1 disabled languages.
-
-		s := m.s.h.resolveSite(fi.Meta().Lang)
-		f := source.NewFileInfo(fi)
-		h := s.h
-
-		// Make sure the layouts are initialized.
-		if _, err := h.init.layouts.Do(context.Background()); err != nil {
+		pc, rc, err := m.addPagesFromGoTmplFi(fi, buildConfig)
+		pageCount += pc
+		resourceCount += rc
+		if err != nil {
 			addErr = err
 			return
 		}
-		if err := func() error {
-			contentAdapter := s.pageMap.treePagesFromTemplateOptions.Get(pi.Base())
-			var rebuild bool
-			if contentAdapter != nil {
-				// Rebuild
-				contentAdapter = contentAdapter.CloneForGoTmpl(fi)
-				rebuild = true
-			} else {
-				contentAdapter = pagesfromdata.NewPagesFromTemplate(
-					pagesfromdata.PagesFromTemplateOptions{
-						GoTmplFi: fi,
-						Site:     s,
-						DepsFromSite: func(s page.Site) pagesfromdata.PagesFromTemplateDeps {
-							ss := s.(*Site)
-							return pagesfromdata.PagesFromTemplateDeps{
-								TmplFinder: ss.TextTmpl(),
-								TmplExec:   ss.Tmpl(),
-							}
-						},
-						DependencyManager: s.Conf.NewIdentityManager("pagesfromdata"),
-						Watching:          s.Conf.Watching(),
-						HandlePage: func(pt *pagesfromdata.PagesFromTemplate, pc *pagemeta.PageConfig) error {
-							s := pt.Site.(*Site)
-							pc.Path = path.Join(pt.GoTmplFi.Meta().PathInfo.Base(), pc.Path)
-							if err := pc.Compile(true, "", s.conf.MediaTypes.Config); err != nil {
-								return err
-							}
-
-							ps, pi, err := h.newPage(
-								&pageMeta{
-									f: f,
-									s: s,
-									pageMetaParams: &pageMetaParams{
-										pageConfig: pc,
-									},
-								},
-							)
-							if err != nil {
-								return err
-							}
-
-							if ps == nil {
-								// Disabled page.
-								return nil
-							}
-
-							u, n, replaced := s.pageMap.treePages.InsertIntoValuesDimensionWithLock(pi.Base(), ps)
-
-							if h.isRebuild() {
-								if replaced {
-									pt.AddChange(n.GetIdentity())
-								} else {
-									pt.AddChange(u.GetIdentity())
-								}
-							}
-
-							return nil
-						},
-						HandleResource: func(pt *pagesfromdata.PagesFromTemplate, rc *pagemeta.ResourceConfig) error {
-							s := pt.Site.(*Site)
-							rc.Path = path.Join(pt.GoTmplFi.Meta().PathInfo.Base(), rc.Path)
-							if err := rc.Compile(s.Conf.PathParser()); err != nil {
-								return err
-							}
-							rs := &resourceSource{path: rc.PathInfo, rc: rc, opener: nil, fi: nil, langIndex: s.languagei}
-
-							_, n, replaced := s.pageMap.treeResources.InsertIntoValuesDimensionWithLock(rc.Path, rs)
-
-							if h.isRebuild() && replaced {
-								pt.AddChange(n.GetIdentity())
-							}
-							return nil
-						},
-					},
-				)
-
-				s.pageMap.treePagesFromTemplateOptions.Insert(pi.Base(), contentAdapter)
-
-			}
-
-			handleBuildInfo := func(s *Site, bi pagesfromdata.BuildInfo) {
-				resourceCount += bi.NumResourcesAdded
-				pageCount += bi.NumPagesAdded
-				s.handleContentAdapterChanges(bi, whatChanged)
-			}
-
-			// TODO1 do we need a mutex?
-			bi, err := contentAdapter.Execute(context.Background())
-			if err != nil {
-				return err
-			}
-			handleBuildInfo(s, bi)
-
-			if !rebuild && bi.EnableAllLanguages {
-				// Clone and insert the adapter for the other sites.
-				for _, ss := range s.h.Sites {
-					if s == ss {
-						continue
-					}
-
-					clone := contentAdapter.CloneForSite(ss)
-
-					// Make sure it gets executed for the first time.
-					bi, err := clone.Execute(context.Background())
-					if err != nil {
-						return err
-					}
-					handleBuildInfo(ss, bi)
 
-					// Insert into the correct language tree so it get rebuilt on changes.
-					ss.pageMap.treePagesFromTemplateOptions.Insert(pi.Base(), clone)
-
-				}
-			}
-
-			return nil
-		}(); err != nil {
-			addErr = err
-			return
-		}
 	default:
 		m.s.Log.Trace(logg.StringFunc(
 			func() string {
@@ -400,6 +267,151 @@ func (m *pageMap) AddFi(fi hugofs.FileMetaInfo, whatChanged *whatChanged) (pageC
 	return
 }
 
+func (m *pageMap) addPagesFromGoTmplFi(fi hugofs.FileMetaInfo, buildConfig *BuildCfg) (pageCount uint64, resourceCount uint64, addErr error) {
+	meta := fi.Meta()
+	pi := meta.PathInfo
+
+	m.s.Log.Trace(logg.StringFunc(
+		func() string {
+			return fmt.Sprintf("insert pages from data file: %q", fi.Meta().Filename)
+		},
+	))
+
+	if !files.IsGoTmplExt(pi.Ext()) {
+		addErr = fmt.Errorf("unsupported data file extension %q", pi.Ext())
+		return
+	}
+	// TODO1 disabled languages.
+
+	s := m.s.h.resolveSite(fi.Meta().Lang)
+	f := source.NewFileInfo(fi)
+	h := s.h
+
+	// Make sure the layouts are initialized.
+	if _, err := h.init.layouts.Do(context.Background()); err != nil {
+		addErr = err
+		return
+	}
+
+	contentAdapter := s.pageMap.treePagesFromTemplateOptions.Get(pi.Base())
+	var rebuild bool
+	if contentAdapter != nil {
+		// Rebuild
+		contentAdapter = contentAdapter.CloneForGoTmpl(fi)
+		rebuild = true
+	} else {
+		contentAdapter = pagesfromdata.NewPagesFromTemplate(
+			pagesfromdata.PagesFromTemplateOptions{
+				GoTmplFi: fi,
+				Site:     s,
+				DepsFromSite: func(s page.Site) pagesfromdata.PagesFromTemplateDeps {
+					ss := s.(*Site)
+					return pagesfromdata.PagesFromTemplateDeps{
+						TmplFinder: ss.TextTmpl(),
+						TmplExec:   ss.Tmpl(),
+					}
+				},
+				DependencyManager: s.Conf.NewIdentityManager("pagesfromdata"),
+				Watching:          s.Conf.Watching(),
+				HandlePage: func(pt *pagesfromdata.PagesFromTemplate, pc *pagemeta.PageConfig) error {
+					s := pt.Site.(*Site)
+					pc.Path = path.Join(pt.GoTmplFi.Meta().PathInfo.Base(), pc.Path)
+					if err := pc.Compile(true, "", s.conf.MediaTypes.Config); err != nil {
+						return err
+					}
+
+					ps, pi, err := h.newPage(
+						&pageMeta{
+							f: f,
+							s: s,
+							pageMetaParams: &pageMetaParams{
+								pageConfig: pc,
+							},
+						},
+					)
+					if err != nil {
+						return err
+					}
+
+					if ps == nil {
+						// Disabled page.
+						return nil
+					}
+
+					u, n, replaced := s.pageMap.treePages.InsertIntoValuesDimensionWithLock(pi.Base(), ps)
+
+					if h.isRebuild() {
+						if replaced {
+							pt.AddChange(n.GetIdentity())
+						} else {
+							pt.AddChange(u.GetIdentity())
+						}
+					}
+
+					return nil
+				},
+				HandleResource: func(pt *pagesfromdata.PagesFromTemplate, rc *pagemeta.ResourceConfig) error {
+					s := pt.Site.(*Site)
+					rc.Path = path.Join(pt.GoTmplFi.Meta().PathInfo.Base(), rc.Path)
+					if err := rc.Compile(s.Conf.PathParser()); err != nil {
+						return err
+					}
+					rs := &resourceSource{path: rc.PathInfo, rc: rc, opener: nil, fi: nil, langIndex: s.languagei}
+
+					_, n, replaced := s.pageMap.treeResources.InsertIntoValuesDimensionWithLock(rc.Path, rs)
+
+					if h.isRebuild() && replaced {
+						pt.AddChange(n.GetIdentity())
+					}
+					return nil
+				},
+			},
+		)
+
+		s.pageMap.treePagesFromTemplateOptions.Insert(pi.Base(), contentAdapter)
+
+	}
+
+	handleBuildInfo := func(s *Site, bi pagesfromdata.BuildInfo) {
+		resourceCount += bi.NumResourcesAdded
+		pageCount += bi.NumPagesAdded
+		s.handleContentAdapterChanges(bi, buildConfig)
+	}
+
+	// TODO1 do we need a mutex?
+	bi, err := contentAdapter.Execute(context.Background())
+	if err != nil {
+		addErr = err
+		return
+	}
+	handleBuildInfo(s, bi)
+
+	if !rebuild && bi.EnableAllLanguages {
+		// Clone and insert the adapter for the other sites.
+		for _, ss := range s.h.Sites {
+			if s == ss {
+				continue
+			}
+
+			clone := contentAdapter.CloneForSite(ss)
+
+			// Make sure it gets executed for the first time.
+			bi, err := clone.Execute(context.Background())
+			if err != nil {
+				addErr = err
+				return
+			}
+			handleBuildInfo(ss, bi)
+
+			// Insert into the correct language tree so it get rebuilt on changes.
+			ss.pageMap.treePagesFromTemplateOptions.Insert(pi.Base(), clone)
+
+		}
+	}
+
+	return
+}
+
 // The home page is represented with the zero string.
 // All other keys starts with a leading slash. No trailing slash.
 // Slashes are Unix-style.
diff --git a/hugolib/hugo_sites_build.go b/hugolib/hugo_sites_build.go
index 43ac2bedb82..ba7c65e6eee 100644
--- a/hugolib/hugo_sites_build.go
+++ b/hugolib/hugo_sites_build.go
@@ -116,7 +116,7 @@ func (h *HugoSites) Build(config BuildCfg, events ...fsnotify.Event) error {
 	conf := &config
 	if conf.whatChanged == nil {
 		// Assume everything has changed
-		conf.whatChanged = &whatChanged{needsPagesAssemble: true}
+		conf.whatChanged = &whatChanged{needsPagesAssembly: true}
 	}
 
 	var prepareErr error
@@ -224,7 +224,7 @@ func (h *HugoSites) initRebuild(config *BuildCfg) error {
 	})
 
 	for _, s := range h.Sites {
-		s.resetBuildState(config.whatChanged.needsPagesAssemble)
+		s.resetBuildState(config.whatChanged.needsPagesAssembly)
 	}
 
 	h.reset(config)
@@ -243,7 +243,7 @@ func (h *HugoSites) process(ctx context.Context, l logg.LevelLogger, config *Bui
 		// This is a rebuild
 		return h.processPartial(ctx, l, config, init, events)
 	}
-	return h.processFull(ctx, l, *config)
+	return h.processFull(ctx, l, config)
 }
 
 // assemble creates missing sections, applies aggregate values (e.g. dates, cascading params),
@@ -252,11 +252,9 @@ func (h *HugoSites) assemble(ctx context.Context, l logg.LevelLogger, bcfg *Buil
 	l = l.WithField("step", "assemble")
 	defer loggers.TimeTrackf(l, time.Now(), nil, "")
 
-	if !bcfg.whatChanged.needsPagesAssemble {
-		changes := bcfg.whatChanged.Changes()
-
+	if !bcfg.whatChanged.needsPagesAssembly {
+		changes := bcfg.whatChanged.Drain()
 		if len(changes) > 0 {
-			// TODO1 consolidate.
 			if err := h.resolveAndClearStateForIdentities(ctx, l, nil, changes); err != nil {
 				return err
 			}
@@ -287,7 +285,7 @@ func (h *HugoSites) assemble(ctx context.Context, l logg.LevelLogger, bcfg *Buil
 		return err
 	}
 
-	changes := bcfg.whatChanged.Changes()
+	changes := bcfg.whatChanged.Drain()
 
 	// Changes from the assemble step (e.g. lastMod, cascade) needs a re-calculation
 	// of what needs to be re-built.
@@ -794,7 +792,6 @@ func (h *HugoSites) processPartial(ctx context.Context, l logg.LevelLogger, conf
 		case files.ComponentFolderAssets:
 			logger.Println("Asset changed", pathInfo.Path())
 			changes = append(changes, pathInfo)
-			needsPagesAssemble = true
 		case files.ComponentFolderData:
 			logger.Println("Data changed", pathInfo.Path())
 
@@ -802,7 +799,6 @@ func (h *HugoSites) processPartial(ctx context.Context, l logg.LevelLogger, conf
 			// Currently very coarse grained.
 			changes = append(changes, siteidentities.Data)
 			h.init.data.Reset()
-			needsPagesAssemble = true
 		case files.ComponentFolderI18n:
 			logger.Println("i18n changed", pathInfo.Path())
 			i18nChanged = true
@@ -886,7 +882,7 @@ func (h *HugoSites) processPartial(ctx context.Context, l logg.LevelLogger, conf
 	resourceFiles := h.fileEventsContentPaths(addedOrChangedContent)
 
 	changed := &whatChanged{
-		needsPagesAssemble: needsPagesAssemble,
+		needsPagesAssembly: needsPagesAssemble,
 		identitySet:        make(identity.Identities),
 	}
 	changed.Add(changes...)
@@ -909,10 +905,7 @@ func (h *HugoSites) processPartial(ctx context.Context, l logg.LevelLogger, conf
 		}
 	}
 
-	// Removes duplicates.
-	changes = changed.identitySet.AsSlice()
-
-	if err := h.resolveAndClearStateForIdentities(ctx, l, cacheBusterOr, changes); err != nil {
+	if err := h.resolveAndClearStateForIdentities(ctx, l, cacheBusterOr, changed.Drain()); err != nil {
 		return err
 	}
 
@@ -940,7 +933,7 @@ func (h *HugoSites) processPartial(ctx context.Context, l logg.LevelLogger, conf
 	}
 
 	if resourceFiles != nil {
-		if err := h.processFiles(ctx, l, *config, resourceFiles...); err != nil {
+		if err := h.processFiles(ctx, l, config, resourceFiles...); err != nil {
 			return err
 		}
 	}
@@ -965,7 +958,7 @@ func (h *HugoSites) LogServerAddresses() {
 	}
 }
 
-func (h *HugoSites) processFull(ctx context.Context, l logg.LevelLogger, config BuildCfg) (err error) {
+func (h *HugoSites) processFull(ctx context.Context, l logg.LevelLogger, config *BuildCfg) (err error) {
 	if err = h.processFiles(ctx, l, config); err != nil {
 		err = fmt.Errorf("readAndProcessContent: %w", err)
 		return
@@ -973,19 +966,20 @@ func (h *HugoSites) processFull(ctx context.Context, l logg.LevelLogger, config
 	return err
 }
 
-func (s *Site) handleContentAdapterChanges(bi pagesfromdata.BuildInfo, whatChanged *whatChanged) {
+func (s *Site) handleContentAdapterChanges(bi pagesfromdata.BuildInfo, buildConfig *BuildCfg) {
 	if !s.h.isRebuild() {
 		return
 	}
 
 	if len(bi.ChangedIdentities) > 0 {
-		whatChanged.Add(bi.ChangedIdentities...)
+		buildConfig.whatChanged.Add(bi.ChangedIdentities...)
+		buildConfig.whatChanged.needsPagesAssembly = true
 	}
 
 	for _, p := range bi.DeletedPaths {
 		pp := path.Join(bi.Path.Base(), p)
 		if v, ok := s.pageMap.treePages.Delete(pp); ok {
-			whatChanged.Add(v.GetIdentity())
+			buildConfig.whatChanged.Add(v.GetIdentity())
 		}
 	}
 }
@@ -999,7 +993,7 @@ func (h *HugoSites) processContentAdaptersOnRebuild(ctx context.Context, buildCo
 				return err
 			}
 			s := p.Site.(*Site)
-			s.handleContentAdapterChanges(bi, buildConfig.whatChanged)
+			s.handleContentAdapterChanges(bi, buildConfig)
 			return nil
 		},
 	})
@@ -1014,7 +1008,7 @@ func (h *HugoSites) processContentAdaptersOnRebuild(ctx context.Context, buildCo
 	return g.Wait()
 }
 
-func (s *HugoSites) processFiles(ctx context.Context, l logg.LevelLogger, buildConfig BuildCfg, filenames ...pathChange) error {
+func (s *HugoSites) processFiles(ctx context.Context, l logg.LevelLogger, buildConfig *BuildCfg, filenames ...pathChange) error {
 	if s.Deps == nil {
 		panic("nil deps on site")
 	}
@@ -1024,7 +1018,7 @@ func (s *HugoSites) processFiles(ctx context.Context, l logg.LevelLogger, buildC
 	// For inserts, we can pick an arbitrary pageMap.
 	pageMap := s.Sites[0].pageMap
 
-	c := newPagesCollector(ctx, s.h, sourceSpec, s.Log, l, pageMap, buildConfig.whatChanged, filenames)
+	c := newPagesCollector(ctx, s.h, sourceSpec, s.Log, l, pageMap, buildConfig, filenames)
 
 	if err := c.Collect(); err != nil {
 		return err
diff --git a/hugolib/pages_capture.go b/hugolib/pages_capture.go
index 10e813fab8f..96c2c0f96e2 100644
--- a/hugolib/pages_capture.go
+++ b/hugolib/pages_capture.go
@@ -42,7 +42,7 @@ func newPagesCollector(
 	logger loggers.Logger,
 	infoLogger logg.LevelLogger,
 	m *pageMap,
-	whatChanged *whatChanged,
+	buildConfig *BuildCfg,
 	ids []pathChange,
 ) *pagesCollector {
 	return &pagesCollector{
@@ -53,7 +53,7 @@ func newPagesCollector(
 		sp:          sp,
 		logger:      logger,
 		infoLogger:  infoLogger,
-		whatChanged: whatChanged,
+		buildConfig: buildConfig,
 		ids:         ids,
 		seenDirs:    make(map[string]bool),
 	}
@@ -70,7 +70,7 @@ type pagesCollector struct {
 
 	fs afero.Fs
 
-	whatChanged *whatChanged
+	buildConfig *BuildCfg
 
 	// List of paths that have changed. Used in partial builds.
 	ids      []pathChange
@@ -121,7 +121,7 @@ func (c *pagesCollector) Collect() (collectErr error) {
 	c.g = rungroup.Run[hugofs.FileMetaInfo](c.ctx, rungroup.Config[hugofs.FileMetaInfo]{
 		NumWorkers: numWorkers,
 		Handle: func(ctx context.Context, fi hugofs.FileMetaInfo) error {
-			numPages, numResources, err := c.m.AddFi(fi, c.whatChanged)
+			numPages, numResources, err := c.m.AddFi(fi, c.buildConfig)
 			if err != nil {
 				return hugofs.AddFileInfoToError(err, fi, c.fs)
 			}
diff --git a/hugolib/pagesfromdata/pagesfromgotmpl_integration_test.go b/hugolib/pagesfromdata/pagesfromgotmpl_integration_test.go
index 55e7c3334d2..eaec99f0bc4 100644
--- a/hugolib/pagesfromdata/pagesfromgotmpl_integration_test.go
+++ b/hugolib/pagesfromdata/pagesfromgotmpl_integration_test.go
@@ -106,7 +106,7 @@ func TestPagesFromGoTmplBasic(t *testing.T) {
 		// Dates
 		"Dates: Date: 2023-03-01|Lastmod: 2023-03-01|PublishDate: 2023-03-01|ExpiryDate: 0001-01-01|",
 	)
-	b.AssertFileContent("public/docs/p2/index.html", "Single: p2|", "<b>Hello World!</b> No **markdown** here.")
+	b.AssertFileContent("public/docs/p2/index.html", "Single: p2title|", "<b>Hello World!</b> No **markdown** here.")
 	b.AssertFileContent("public/docs/p3/index.html", "<strong>Hello World Default</strong>")
 }
 
@@ -231,15 +231,15 @@ baseURL = "https://example.com"
 func TestPagesFromGoTmplEditGoTmpl(t *testing.T) {
 	t.Parallel()
 	b := hugolib.TestRunning(t, filesPagesFromDataTempleBasic)
-	b.EditFileReplaceAll("content/docs/_content.gotmpl", `"title" "p2"`, `"title" "p2edited"`).Build()
-	b.AssertFileContent("public/docs/p2/index.html", "Single: p2edited|")
-	b.AssertFileContent("public/docs/index.html", "p2edited")
+	b.EditFileReplaceAll("content/docs/_content.gotmpl", `"title" "p2title"`, `"title" "p2titleedited"`).Build()
+	b.AssertFileContent("public/docs/p2/index.html", "Single: p2titleedited|")
+	b.AssertFileContent("public/docs/index.html", "p2titleedited")
 }
 
 func TestPagesFromGoTmplEditDataResource(t *testing.T) {
 	t.Parallel()
 	b := hugolib.TestRunning(t, filesPagesFromDataTempleBasic)
-	b.AssertRenderCountPage(6)
+	b.AssertRenderCountPage(7)
 	b.EditFileReplaceAll("assets/mydata.yaml", "p1: \"p1\"", "p1: \"p1edited\"").Build()
 	b.AssertFileContent("public/docs/p1/index.html", "Single: p1edited:p1|")
 	b.AssertFileContent("public/docs/index.html", "p1edited")
@@ -257,9 +257,8 @@ func TestPagesFromGoTmplEditPartial(t *testing.T) {
 func TestPagesFromGoTmplRemovePage(t *testing.T) {
 	t.Parallel()
 	b := hugolib.TestRunning(t, filesPagesFromDataTempleBasic)
-	//                                        RegularPagesRecursive: p1:p1:/docs/p1|p1:p1:/docs/p3|p2:/docs/p2|pfile:/docs/pfile|$
 	b.EditFileReplaceAll("content/docs/_content.gotmpl", `{{ $.AddPage  (dict "kind" "page" "path" "p2" "title" "p2title" "dates" $dates "content" $contentHTML ) }}`, "").Build()
-	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p3title:/docs/p3|pfile:/docs/pfile|$")
+	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p3title:/docs/p3|p4title:/docs/p4|pfile:/docs/pfile|$")
 }
 
 func TestPagesFromGoTmplDraftPage(t *testing.T) {
@@ -281,9 +280,9 @@ func TestPagesFromGoTmplDraftFlagFromResource(t *testing.T) {
 func TestPagesFromGoTmplMovePage(t *testing.T) {
 	t.Parallel()
 	b := hugolib.TestRunning(t, filesPagesFromDataTempleBasic)
-	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p1:p1:/docs/p3|p2:/docs/p2|pfile:/docs/pfile|$")
+	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p2title:/docs/p2|p3title:/docs/p3|p4title:/docs/p4|pfile:/docs/pfile|$")
 	b.EditFileReplaceAll("content/docs/_content.gotmpl", `"path" "p2"`, `"path" "p2moved"`).Build()
-	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p1:p1:/docs/p3|p2:/docs/p2moved|pfile:/docs/pfile|$")
+	b.AssertFileContent("public/index.html", "RegularPagesRecursive: p1:p1:/docs/p1|p2title:/docs/p2moved|p3title:/docs/p3|p4title:/docs/p4|pfile:/docs/pfile|$")
 }
 
 func TestPagesFromGoTmplEnableAllLanguages(t *testing.T) {
diff --git a/hugolib/site.go b/hugolib/site.go
index 13a1fce124a..d9103e73790 100644
--- a/hugolib/site.go
+++ b/hugolib/site.go
@@ -374,7 +374,7 @@ func (s *Site) watching() bool {
 type whatChanged struct {
 	mu sync.Mutex
 
-	needsPagesAssemble bool
+	needsPagesAssembly bool
 	identitySet        identity.Identities
 }
 
@@ -394,6 +394,10 @@ func (w *whatChanged) Add(ids ...identity.Identity) {
 func (w *whatChanged) Clear() {
 	w.mu.Lock()
 	defer w.mu.Unlock()
+	w.clear()
+}
+
+func (w *whatChanged) clear() {
 	w.identitySet = identity.Identities{}
 }
 
@@ -404,6 +408,14 @@ func (w *whatChanged) Changes() []identity.Identity {
 	return w.identitySet.AsSlice()
 }
 
+func (w *whatChanged) Drain() []identity.Identity {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	ids := w.identitySet.AsSlice()
+	w.clear()
+	return ids
+}
+
 // RegisterMediaTypes will register the Site's media types in the mime
 // package, so it will behave correctly with Hugo's built-in server.
 func (s *Site) RegisterMediaTypes() {
diff --git a/media/mediaType_test.go b/media/mediaType_test.go
index 3b8e099b897..abf0ed91ea9 100644
--- a/media/mediaType_test.go
+++ b/media/mediaType_test.go
@@ -214,3 +214,11 @@ func BenchmarkTypeOps(b *testing.B) {
 
 	}
 }
+
+func TestIsContentFile(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(IsContentFile(filepath.FromSlash("my/file.md")), qt.Equals, true)
+	c.Assert(IsContentFile(filepath.FromSlash("my/file.ad")), qt.Equals, true)
+	c.Assert(IsContentFile(filepath.FromSlash("textfile.txt")), qt.Equals, false)
+}
diff --git a/resources/postpub/fields_test.go b/resources/postpub/fields_test.go
index 336da1f0e3e..53875cb346b 100644
--- a/resources/postpub/fields_test.go
+++ b/resources/postpub/fields_test.go
@@ -36,6 +36,8 @@ func TestCreatePlaceholders(t *testing.T) {
 		"SuffixesCSV": "pre_foo.SuffixesCSV_post",
 		"Delimiter":   "pre_foo.Delimiter_post",
 		"FirstSuffix": "pre_foo.FirstSuffix_post",
+		"IsHTML":      "pre_foo.IsHTML_post",
+		"IsMarkdown":  "pre_foo.IsMarkdown_post",
 		"IsText":      "pre_foo.IsText_post",
 		"String":      "pre_foo.String_post",
 		"Type":        "pre_foo.Type_post",