Merge pull request #35898 from overleaf/dp-visual-markdown-editor-setting

[web] Track markdown editor mode separately and default to visual

GitOrigin-RevId: 7195189c683618b3e0c735f91193fb662078b558

services/web/frontend/js/features/source-editor/utils/file.ts

@@ -48,6 +48,9 @@ export const filterFolders = filterByType('folder')
 
 const IMAGE_FILE_EXTENSIONS = ['png', 'jpg', 'jpeg', 'pdf', 'eps', 'svg']
 
+// File extensions handled by the markdown visual editor.
+export const MARKDOWN_FILE_EXTENSIONS = ['md', 'markdown']
+
 export const getFileExtension = (filename: string): string | null => {
   const parts = filename.split('.')
   if (parts.length < 2) {
@@ -65,6 +68,11 @@ export const isSvgFile = (filename: string): boolean => {
   return getFileExtension(filename) === 'svg'
 }
 
+export const isMarkdownFile = (filename: string): boolean => {
+  const extension = getFileExtension(filename)
+  return extension !== null && MARKDOWN_FILE_EXTENSIONS.includes(extension)
+}
+
 export function isImageFile(file: File) {
   return hasImageExtension(file.name)
 }