Description

I was messing around with /execute, trying to accomplish something completely unrelated to LuckPerms, but stumbled upon this issue anyway. As far as I understand, only vanilla commands can be used in /execute, but the tab-complete menu shows a couple options from LuckPerms. Curious as I am, I started messing around with it, and got an "internal error while attempting to tab-complete this command." The first time I tried, it completely crashed the server.

Reproduction steps

1. Start typing /execute as run
2. Put a LuckPerms command in after run
3. Put in an argument, once you hit space it errors out.

Environment details

• Server type/version: Paper running version 1.16.5 build 603
• LuckPerms version: v5.3.29

Any other relevant details

Here's the gist of the initial crash report
Here's the gist of the console error when trying to autocomplete
Here's a link to a YouTube clip of what I was doing

I thought it would be best to report here because it was a LuckPerms command that caused the issue, but I'm not super great at reading error logs, so if it needs to go somewhere else I'd be glad to post elsewhere.

Strange error, I think if anything it might be a Paper problem. Could you try updating to a newer build to see if it fixes the problem? If not, might be worth reporting it over there.