Note that in the Library (Show All Bookmarks) you only have the Details pane at the bottom right to edit the properties (this is not possible via the context menu), so you would have to use the sidebar (Ctrl+B) or right-click bookmarks or folder in a bookmark drop down list.

That said, you can use code in userChrome.css to hide this section or only expand it when you set focus. That way you can still see more of longer names.

/* detailsPane: hide when not focused */
#detailsPane:not(:focus-within)
:is(#editBMPanel_locationRow, #editBMPanel_tagsRow, #editBMPanel_tagsSelectorRow, #editBMPanel_keywordRow) {
  visibility:collapse;
}

/* detailsPane: always hide */
#detailsPane :is(#editBMPanel_tagsRow, #editBMPanel_tagsSelectorRow) {visibility:collapse !important;}

/* detailsPane: height */
#detailsPane {height:unset !important;}

It is not that difficult to create userChrome.css if you have never used it.

The first step is to open the "Help -> Troubleshooting Information" page and find the button to access the profile folder.

• https://support.mozilla.org/en-US/kb/use-troubleshooting-information-page-fix-firefox

You can find this button under the "Application Basics" section as "Profile Folder -> Open Folder". If you click this button then you open the profile folder in the Windows File Explorer. You need to create a folder with the name chrome in this folder (name is all lowercase). In the chrome folder you need to create a plain text file with the name userChrome.css (name is case sensitive). In this userChrome.css text file you paste the text posted. On Mac you can use the TextEdit utility to create the userChrome.css file as a plain text file.

In Windows saving the file is usually the only time things get more complicated because Windows can silently add a .txt file extension and you end up with a file named userChrome.css.txt. To avoid this you need to make sure to select "All files" in the dialog to save the file in the text editor using "Save File as".

You need to close (Quit/Exit) and restart Firefox when you create or modify the userChrome.css file.

See also:

• https://www.userchrome.org/what-is-userchrome-css.html
• userContent.css/how-create-userchrome-css.html

In Firefox 69 and later you need to set this pref to true on the about:config page to enable userChrome.css and userContent.css in the chrome folder.

• toolkit.legacyUserProfileCustomizations.stylesheets = true

• https://www.userchrome.org/firefox-changes-userchrome-css.html

I don’t see anything called Library. I just open FF, click on Bookmarks, and then click on Show All Bookmarks. I get 3 panels displayed. There’s a left side column & that’s OK.

But the rest of the screen has an upper panel that displays the Name & URL, and a lower panel that shows all the editing information & which takes up about a third of the screen.

I never use that screen so am not familiar with it, but my wife likes to use it & said the bottom third was never filled with all that stuff until the other day. She said the Name & URL panel used to fill the area top to bottom.

In this other thread & elsewhere I saw the comment “click the More button in the Details pane at the bottom right.” I figured that might give me some options, but I don’t have a “More” button. Am I suppose to? https://support.mozilla.org/en-US/questions/1051586

I have used userChrome.css & will use it unless there is something in the “about:config” that controls that lower panel.

Thanks for the suggestion.

Library is the name for the Bookmarks and History Manager that you open via "Show All Bookmarks" (Ctrl+Shift+O).

• https://support.mozilla.org/en-US/kb/bookmarks-firefox

This window has a details pane at the bottom right that allows to inspect and edit the properties of the currently selected bookmark item. This Details panel has always been there, but a long time ago you could collapse most of its content via the More button you mentioned.

You can use code like I posted above in userChrome.css to change the way this panel is shown.

When clicking on Show All Bookmarks, the Other Bookmarks folder opens by default, at least on my profiles. When this opens the right side lower part of the screen displays all the edit info which takes up about a third of the screen. If Other Bookmarks is empty, the lower part is empty & takes up only about 20% of the screen.

If I select Bookmarks Menu on the left side the screen, the right side lower part also takes up only about 20% of the screen & just says Bookmarks Menu.

As mentioned, I’m not familiar with that screen & will see if that 20% size detail pane is workable for my wife. If not I'll try the userChrome.css method.

If I want to hide it, do I need to use the full script you posted or just the middle part where it says "detailsPane: always hide"?

Thanks