user27302: In Adobe Premiere, I need sometimes to add some small custom masks. And I need to zoom in the video frame in this case. The only option I found is to manually drug a video panel border.

Are there special hotkeys for these actions (zoom in and zoom out video frame)?

user29988: Yes, well not for zooming but for maximizing and restoring the panel. These shortcuts may look different depending on the keyboard layout. On English layouts it's ` for the active frame, which is the frame with the thin blue border drawn around, and Shift+` for the frame under the cursor. The ` character is called acute or backtick.
If you use another keyboard layout and the ` does not work or you want to change the shortcuts, go to Edit menu -> Keyboard Shortcuts... Search for Maximize and you'll get "Maximize or Restore Active Frame" and "Maximize or Restore Frame Under Cursor".
Also, you can set zoom-in/-out shortcuts for the program monitor, but it zooms into the video and doesn't make the panel larger. Those shortcuts are not set by default.

27302: <p>In Adobe Premiere, I need sometimes to add some small custom masks. And I need to zoom in the video frame in this case. The only option I found is to manually drug a video panel border.</p>
<p><a href="https://i.stack.imgur.com/XFlkh.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XFlkh.gif" alt="enter image description here" /></a></p>
<p>Are there special hotkeys for these actions (zoom in and zoom out video frame)?</p>
 29988: <p>Yes, well not for zooming but for maximizing and restoring the panel. These shortcuts may look different depending on the keyboard layout. On English layouts it's ` for the active frame, which is the frame with the thin blue border drawn around, and Shift+` for the frame under the cursor. The ` character is called acute or backtick.</p>
<p>If you use another keyboard layout and the ` does not work or you want to change the shortcuts, go to Edit menu -&gt; Keyboard Shortcuts... Search for <em>Maximize</em> and you'll get &quot;Maximize or Restore Active Frame&quot; and &quot;Maximize or Restore Frame Under Cursor&quot;.</p>
<p>Also, you can set zoom-in/-out shortcuts for the program monitor, but it zooms into the video and doesn't make the panel larger. Those shortcuts are not set by default.</p>
