Minecraft Version

1.19.x

Version

1.101.1

Details

Reproduction steps:

1. Place down a turtle in any world.
   Logs:
   latest.log

The turtles stopped working mysteriously, they used to work.
The same enviorement.

See #1239. This is an Optifine bug: they don't support the latest version of Forge. You can probably downgrade to Forge 43.1.1, though really I'd recommend switching to Occulus instead.

Older versions of forge are incompatible with mods that are being used.

ah wait no one cares anyway

One thing;
The game only crashes when placing a turtle, and not computers. Computers are blocks with UI as well, and they are technically block entities as well.

older forge does not boot up.

probably mod incompatiblibylty

where is the delete issue button?

You might be able to switch to Forge 43.1.52 as long as you're running OptiFine HD U I1. You have to be careful to run the exact version of Forge mentioned on OptiFine's download page, otherwise you'll occasionally run into issues like these.

Though I'd also recommend looking into the various Optifine alternatives out there. Optifine is notoriously prone to issues like these - mods like Oculus for shaders and Rubidium are much better supported.