organizing bookmarks

The official instructions say to put a bookmark in a folder click on three dots, click to edit, then click on either a particular folder or some non-existent generic folder button. In my version of android Firefox, neither alternative is possible. If I go from the edit bookmark screen to the preceding general screen (where the folders are listed) and click on a folder, both happens, the bookmark is not transferred to the folder. As for the second, one is told to open the edit function and then click on the folder button. But there is no folder button. How to do it? I'm running android 14 on a Galaxy A14.