You can access bookmark all tabs by right-clicking on a tab, or use the keyboard shortcut Control+Shift+D

fabulous! thank you

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Some menu entries are hidden by default and only appear if you use the keyboard to open the menu.
"Bookmark All Tabs" and "Bookmark All Tabs" in the Bookmarks menu are among them.

You can see the difference if you use Alt+F or Alt+B to the File and Bookmarks menu and compare that to what you see if you use the mouse to open the menu after you have made the menu bar visible by pressing Alt or by pressing F10.

• "Bookmark This Page" and "Bookmark All Tabs" no longer show in the Bookmarks menu unless you open the Bookmarks menu via the keyboard (Alt + B).
• "Bookmark This Page" can be accessed via the right-click context menu of that browser page.
• "Bookmark All Tabs" can be accessed via the right-click context menu of a tab on the tab bar.