There is a star like button next to the search bar on the Navigation Toolbar to bookmark the current web page and a "Show your bookmarks" button next to it to open the Bookmarks in a drop down menu.

You can find "Show All Bookmarks" to open the Bookmarks Manager (Library) at near the top of the drop-down list.

If you bookmark a page then "Bookmark This Page" in the Bookmarks menu as well as the tooltip of the star changes to "Edit This Bookmark" and the star is highlighted blue.

• https://support.mozilla.org/kb/how-do-i-use-bookmarks

Hi, also note that if the bookmarks button is missing, open the 3-bar menu > Customize, and if you can see it, you can drag it to a toolbar in the location of your choice > Exit Customize to save.

If it isn't in there, whilst in customize mode, click on Restore Defaults. More in Customize Firefox controls, buttons and toolbars.

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