I'm using the javacv library with compose for desktop, but when I run the project, I get an error: "CreateProcess error=206, The filename or extension is too long when running".

Are you able to run it in a normal java project?

Are you using Windows? Is your absolute path of any file longer than 260 charactes?

Individually they work fine, but together they don't work.

What do you mean by "together"? As in "merged"? In that case, let me ask once again - are the resulting paths (in their absolute form) longer than 260 characters?

No

are you running the project from the IDE or from Gradle? Gradle should have a built-in workaround for Windows path limitations, and IDEA has a configurable option: https://blog.jetbrains.com/idea/2017/10/intellij-idea-2017-3-eap-configurable-command-line-shortener-and-more/

IDE. The project does not start, this error just comes out in ide

then modify the run configuration, as shown in the link I posted

thank you very much. Everything is working