TTF fonts in the action bar render above the GUI background

The bug

When rendering text in the action bar with a TrueType font, the text is drawn on top of an open GUI. The test action bar message appears fully lit despite being behind the inventory's background, as visible in the attached screenshot.

Specifically, this only occurs if the action bar is the last element to be drawn before the GUI. If a chat message or subtitle is visible, the issue does not occur. Based on analyzing the source code, the chat and subtitles are drawn after the action bar, so it's likely related to the action bar being the last element drawn.

Steps to reproduce

1. Apply the attached resource pack.

2. Run the following command in a command block so there is no chat message, or quickly press F3 + D after to clear the chat:

   title @a actionbar {text:"test",font:"test:hud"}

3. Open an inventory — for example, by pressing E.

4. Notice that when there is no chat message or subtitle showing, the text renders on top of the background.

Observed behavior

The action bar's TTF text will render in front; any non-TTF text will be rendered properly.

Expected behavior

The action bar would render behind the GUI's background.