Cleaning up Bookmarks menu

[surveyor 7]

I'm migrating from an ancient Firefox, and I'm trying to make everything (reasonable) look like it did.

Export bookmarks as HTML from Firefox, import HTML to Pale Moon.

I had the Bookmarks Toolbar hidden, and it was easy enough to hide in Pale Moon. Then I went to suppress entries in the Bookmarks menu, and had more trouble. I wanted to hide "subscribe to this page", "bookmarks toolbar", and "unsorted bookmarks", so I searched on the forum and couldn't find anything that worked. Some posts did remind me of chrome/userChrome.css where I'd hid them in Firefox long ago, but the same stanza didn't work in Pale Moon. Eventually I searched the Mozilla forums and got bits and pieces and trial and error and eventual success. To save anybody else time, I ended up with

#subscribeToPageMenuitem,
#subscribeToPageMenupopup,
#bookmarksToolbarFolderMenu,
#bookmarksToolbarFolderMenu + menuseparator,
#menu_unsortedBookmarks,
#bookmarksMenuPopup > menuseparator[builder="end"]
{
display: none !important;
}