This bug is affecting me. It happens exactly like this in Ubuntu 20.04 LTS and in Pop!_OS.

+++ This bug was initially created as a clone of Bug #1689423 +++

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:85.0) Gecko/20100101 Firefox/85.0

Steps to reproduce:

Create a new bookmark in the toolbar if your don't have any
Right click on the space between the address bar and the buttons on the right
Select 'Bookmarks toolbar' -> 'Only Show on new Tab'
Create new tab
Bookmark toolbar is not showing up

Actual results:

Bookmark toolbar is not showing up when 'Only Show on new Tab' is selected

Expected results:

When creating new tab with 'Only Show on new Tab' select, a bookmark toolbar should show up when creating new tab

The Bugbug bot thinks this bug should belong to the 'Firefox::Bookmarks & History' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

This bug does not occur on a private window. If I open a tab on a private window, I see the bookmarks. I disabled all of my extensions, thinking that one extension is at fault. I still can't see the bookmarks on a normal window.

What is your new tab page set to, is it Firefox Home or a blank page?

Blank page.

Thank you, this is already filed and tracked in bug 1676492