Bravo !!! Job well done

Tried to use it and all I got was "Wait background load" I cannot even uninstall it from Firefox! I get a gray box with a dot in the center of it on the Firefox Add-ons page.

Indispensable add-on.
One small problem when I (mistakenly) open two Properties dialogs for the same bookmark.
1. Create a bookmark "testA" and press Save.
2. Right-click the bookmark "testA" and open Properties. Let's call this dialog2.
3. Right-click the bookmark "testA" again and open Properties. Let's call this dialog3.
4. Edit the title of dialog3 to "testB" and Save. The bookmark correctly changes to "testB".
5. Switch the focus to dialog2.
6. Don't edit dialog2 and just press its Cancel or X button. It will close.
7. But then, the bookmark automatically changes its title back to "testA".
I expect it to keep "testB", because I pressed Cancel for dialog2.

(Reply to Developer response):
Yes, limiting property windows to single instances sounds better.
Additional note. I called it a "dialog", but unlike modal dialogs, it is actually a non-modal window, and this is very convenient because I can copy and paste multiple text and URL from the browser's webpage into the properies, and vice versa. I can even swap multiple portions between two bookmarks. So keep it non-modal, if possible.

(Reply to update 05/11/2023)
Dialog in 2.0.119 works as expected.
I also add my thanks for your implementing the Undo feature.

Goergeous tool! Been looking for regex and some "show-my-bookmark-in-its-tree-location" functionality. And 'bmsp2' has both. Thank you very much, Chris

There is a problem with the way the favicon is obtained.
First, open a bookmark that has already acquired a favicon.
Then open another bookmark in the same tab before the page finishes loading.
Then the acquired favicon disappears.
Please fix this problem.

------------------------
The above issue seems to have been resolved. thank you.

However, there was another problem.
Unable to open external file bookmarks.
for example,
file:///D:/Download/WebScrapBook/data/20230405010758065/index.html
I can't open bookmarks starting with 'file:///' like this.
Please fix it.

The Firefox Bookmark Sidebar already kicks butt. This Add-On takes it to a whole new level. I am seriously impressed (🡰 Initial Review - 2023-03-28).

Edit (2023-07-27). After 4 months of use now, I just keep getting blown away by how amazing this Add-On is. More often than not in reviews, through time, ratings go down. I believe this is the first time I've actively come back to a review to praise it even more. If I could give a 6 star rating, I would. Amazing job aaFn.

This functionality should be built into Firefox Bookmarks. I'm very grateful this add-on exists. Was driving myself mad right clicking the item i searched and then clicking show in folder. Now if only there was an add-on to find duplicates in folders... haha

Un incontournable.
Parfait en tous points.

I have just started using this and I absolutely love it, especially being able to see which folder a bookmark is saved in. The only issues I have found so far are:

1) I have 'Remember size of resizeable objects' checked but the search pane isn't permanent (it is with the bookmark Properties window). If I close then re-open the bookmarks sidebar, the search resize is lost. If I choose another entry from the sidebar dropdown (eg: Bookmarks, History) then return to BSP2, the search resize is lost. There is nothing in Options that says this is expected behaviour so, if it is, can a note please be added to specify this.

2) Closing and reopening the bookmark sidebar, or choose another entry from the sidebar dropdown and returning to BSP2, doesn't retain the scroll position in the bookmark list.

IN RESPONSE TO YOUR REPLY:
1) Thank you for investigating.
2) No, you are not misunderstanding. I see that the scroll returns to center. That's all good if it's expected behaviour. At least it hasn't been scrolled out of view.

When you have a forest of book marks like I do you will lose track of where certain bookmarks are, and this is the only extension I've found so far that helps you find them. Can't imagine life without it!

Thank you for your labor of love, aaFn! It's great for finding those stray bookmarks. Can it also search on the Tag field?

Great extension but currently won't load: "XML Parsing Error: no root element found
Location: chrome://browser/content/webext-panels.xhtml
Line Number 1, Column 1"
Update: Restarting Firefox cured the issue.