Possible GPL violation

[p91paul]

I believe that the very first clause of the GPL

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.

is violated by your modification at the top of the document

You can use the code from this project to customize your own plugins,
but are not allowed to publish to the JetBrains Marketplace platform

I believe the FSF wrote the GNU GPL to be adopted by free software projects as-is, and even license documents are covered by copyright.

If you want to make a nonfree software (and disallowing republishing it is clearly a non-free clause, and even goes against the open source definition https://opensource.org/osd), you should write your own licence. Tricking people into believing this is open source/free software by using a well-known license and modifying it is quite misleading.

[obiscr]

Thanks for pointing this out, I'll fix it.