Fails to update browser history button state

[nyanpasu64]

Firefox 63.0b10 (64-bit), Windows 10.

If I click on an image, the activation status of back/forward buttons is not updated.

• If the back button is grayed and I click an image, the back button remains grayed and alt+left fails.
• If the forward button is active and I click, it remains active even though there are no future pages (alt+right does nothing).

Right-clicking the back/forward button allows correct history navigation.