The profile folder should be the same for any of the desktop platforms (Windows, Mac or Linux). Though, the location of the folder itself won't be the same on Windows as it is on Mac, since the two operating systems store application data in two different locations.

Generally, it's not a good idea to transfer the entire folder. Some of the files reference specific file locations that may not be in the same location on different devices. It's usually only recommended to transfer the files and folders listed on the Profiles - Where Firefox stores your bookmarks, passwords and other user data page, since those are the files that have the important data in the profile folder.

Hope this helps.

Best is to copy only a few selected database files and avoid copying files like prefs.js and pkcs11.txt that can contain absolute file paths and other platform specific data. Note that you only need the profile stored in "AppData\Roaming" on Windows.

Location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>
• ~/Library/Application Support/Firefox/Profiles/<profile>

You can copy certain files with Firefox closed to the current profile folder to transfer or recover personal data.

• bookmarks and history: places.sqlite
• favicons: favicons.sqlite
• bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
• cookies.sqlite for the Cookies
• formhistory.sqlite for saved autocomplete Form Data
• logins.json (encrypted logins;32+) and key4.db (decryption key;58+) for Passwords saved in the Password Manager
  key3.db support ended in 73+; to use key3.db in 58-72, make sure to remove key4.db
• cert9.db (58+) for (intermediate) certificates stored in the Certificate Manager
• persdict.dat for words added to the spell checker dictionary
• permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
• sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

• Help -> Troubleshooting Information -> Profile Folder/Directory:
  Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
• https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data