SCUMM/HE: Flashing line at bottom of screen in Freddi 3

[Thunderforge]

In Freddi Fish 3: The Case of the Stolen Conch Shell, there is a situation in which a flashing line appears at the bottom of screen during some dialogue.

Reproduction Steps

1. Open the debugger and type in room 17
2. Click on the pink fish on the rope in the upper left corner of the screen (do not click on the clam to cut the rope)
3. Luther will say "Gee, that fish looks like it's really hungry for those kelp vines."

During Luther's dialogue, the very bottom of the sreen will have a flashing line. See attached animated GIF

Versions tested

• Freddi Fish 3: Steam release
• ScummVM 2.6.0 nightly 2022-06-02

[Thunderforge]

Turns out this *doesn't* happen in the English-UK version of the game, but it does in the English-US version.