[Header] “View in fullscreen” in actor selector is only focused after reaching the end of the list

**Description**
For keyboard users, the “View in fullscreen” option in the actor selector isn’t focusable until they’ve tabbed through the entire list of actors. This makes navigation less intuitive and could impact accessibility.

This issue is not critical — we’ll wait to address it until after accessibility (UU) user testing has been completed.

**Expected behavior**
Keyboard users should be able to reach and focus the “View in fullscreen” option without having to navigate through the full list of actors.

Locate the actor selector and its “View in fullscreen” option, then reproduce the keyboard tab order described in the issue. Done means keyboard users can focus the fullscreen option without tabbing through the entire actor list.

Written by the indexing model from the issue text.