How can I find out if a project has a GPL-2.0 or GPL-2.0+ license?

Question

Licenses for software and other works

I have a fork of the project -- https://github.com/Mingun/JHexView.

The project has a license file, it's GPL-2.0 -- https://github.com/Mingun/JHexView/blob/master/gpl.txt. The license is not mentioned anywhere else in the project.

Is it possible to somehow understand, based on this information, the license of the project is "only GPL-2.0" or "GPL-2.0 or later"? Compatibility with other licenses depends on this (see https://www.gnu.org/licenses/gpl-faq.html#AllCompa...