User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/109.0

Steps to reproduce:

1. Select a folder or bunch of the folders under "Videos to Watch" in my bookmarks
2. Drag them to a new position

Actual results:

Sometimes, they'll wind up in a position I didn't select, or intermixed with folders near where I dropped them or not moving at all because Firefox resolves the incorrect position I dragged them from as equal to the correct position I dragged them to.

Furthermore, leaving and returning to the folder may also reveal other ordering changes that had been made but not rendered.

Sometimes, it seems to help if I drag a lower bunch of folders up rather than dragging an upper bunch of folders down, but I haven't done an in-depth study of how the "leave and return to the folder to refresh things" part interacts with that, so it's possible I'm just seeing a difference in the transient visual representation of the database state rather than the actual effects on the database state.

I have been completely unable to alphabetically sort my bookmark folders because of this and, when I have time, I'm likely going to work around it by quitting Firefox and writing a Python script to implement "alphabetically sort children of bookmarks folder X" by interfacing with the underlying SQLite database directly and bypassing all the Firefox code that's not subject to SQLite's avionics-grade MC/DC test suite.

Commands like VACUUM and .dump followed by creating a fresh database don't appear to run into any internal consistency issues with the database, though I wasn't willing to risk actually loading the resulting new places.sqlite into Firefox in case there was something Firefox does to it that's not captured in the dump file.

Expected results:

Drag-and-drop reordering should just work.

Hi @Stephan Sokolow , I tried to reproduce this issue on my end on a Windows 10 machine by creating a folder with a lot of subfolders but I never had any issues reordering those subfolders or the bookmarks inside them, can you try and get a screen recording of the issue?
Also what OS are you using ? Is it Ubuntu ?
Does the issue occur in safe mode ? If you are willing to try to reproduce this issue in Safe mode could help us rule out any addons. You can find the steps here: https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

(In reply to Stephan Sokolow from comment #0)

Sometimes, they'll wind up in a position I didn't select

Where are you doing this reordering, in menus, trees, the toolbar?
Is the drop indicator (each view should have one) properly showing the destination but then the bookmark ends elsewhere, or is the indicator also wrong?

Furthermore, leaving and returning to the folder may also reveal other ordering changes that had been made but not rendered.

This seems to indicate some kind of corruption, I'd suggest to start by going to about:support, and run the Integrity Check in the Places Database section, then check if the problem persists after that.

I have been completely unable to alphabetically sort my bookmark folders because of this

You can right click on a folder and choose Sort By Name, that will sort the folder contents by name.

Commands like VACUUM and .dump followed by creating a fresh database don't appear to run into any internal consistency issues

Please don't do this, there's a lot of things in the db that a dump and rebuild is not going to preserve, and long term that will cause exactly this kind of bugs.

can you try and get a screen recording of the issue?

Things have been a bit too busy to do so, but I will when I can make time.

Also what OS are you using ? Is it Ubuntu ?

I'm running the Flatpak build of Firefox on Kubuntu Linux 20.04 LTS.

Does the issue occur in safe mode ? If you are willing to try to reproduce this issue in Safe mode could help us rule out any addons.

Again, I've been busy but I will test this when I can make time.

Where are you doing this reordering, in menus, trees, the toolbar?

Both the tree sidebar and the main pane of the Library window.

Is the drop indicator (each view should have one) properly showing the destination but then the bookmark ends elsewhere, or is the indicator also wrong?

Either the drop indicator is correct but then the bookmark shows up elsewhere (I distinctly remember frustrating moments when I would try to fix the problem and discover that drag-and-drop would have no effect because it was convinced that the starting position WAS where the drop marker was despite them being visibly different) or the bookmark appears to end up in the correct place but it changes when I force it to refresh the view by navigating the library window (there were moments when my workflow was "drag-reorder, navigate away, navigate back, repeat until I get as close to alphabetized as I felt I could).

I don't believe I noticed any difference between dragging in the tree sidebar and dragging in the main pane, given that I would have preferentially used one over the other as a workaround if I had.

This seems to indicate some kind of corruption, I'd suggest to start by going to about:support, and run the Integrity Check in the Places Database section, then check if the problem persists after that.

I'm pretty sure I did that and it found nothing, but I did it again. It says it's sane and coherent.

You can right click on a folder and choose Sort By Name, that will sort the folder contents by name.

facepalm Somehow, I checked the menus up top (Organize, Views, Import and Backup) looking for a way to sort the currently displayed folder, but I must have missed the context menu entry.

Please don't do this, there's a lot of things in the db that a dump and rebuild is not going to preserve, and long term that will cause exactly this kind of bugs.

I suspected there might be, which is why I didn't swap in the resulting new database... just used it as an opportunity to see if SQLite would complain about anything.

I strongly suspect this is a duplicate of bug 1557853. Going to about:support, runing the Integrity Check in the Places Database section and then restarting should help as a workaround.