Firefox on Android has a "Collections" option,it is convenient displaying some websites on the startup page.But "Collections" seems not to be synced.
Syncing collections has been suggested in 2022,but it isn't added to sync list for now.
Alternatively,it can be used as a specific section of the bookmark (but displayed on the startup page), similar to the bookmarks toolbar on PC. This makes it possible to sync frequently useful websites on both mobile and PC devices.
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