User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36
Steps to reproduce:
1. Launch Firefox with a clean profile
2. Verify there is nothing in the Location Bar related to zooming
3. Click the Menu [≡]
4. Click the [+] Customize button
5. Click anywhere on the zoom controls and drag them to the Toolbar
6. Click the [√] Exit Customize button and verify the Zoom Controls still function in the toolbar
7. Verify there is nothing in the Location Bar related to zooming
8. Remove the Zoom Controls from the toolbar and ensure default value is 100% when clicking the Menu [≡]
In the step 8, After removing zoom controls from the toolbar we have to check the default value is 100% But,
NO ZOOM CONTROLS ARE VISIBLE IN THE MENU.
Zoom controls should be visible in the menu with default value 100%.
User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:53.0) Gecko/20100101 Firefox/53.0
I have tested this issue on Windows 10 x64 with the latest Firefox release (50.1.0) and the latest Nightly (53.0a1-20170110075905) and managed to reproduce it.
In the step 8, after removing zoom controls from the toolbar, when check to see if the default value is 100% in the menu, the zooming controls are missing.
This seems to be more of an enhancement than an issue in my opinion.
However, I am assigning a component to this issue in order to involve the development team and get an opinion on this.