https://bugs.freedesktop.org/show_bug.cgi?id=102709
--- Comment #2 from Vitalii shpalikvitalik@gmail.com --- (In reply to Samuel Pitoiset from comment #1)
Well, War Thunder doesn't check that GL_EXT_texture_compression_s3tc is exposed before using those compressed formats.
Though, if you have libtxc_dxtn installed on your system the extension should be enabled, can you check?
I have the same problem with war thunder, but my driver crashes and only hard reboots help. I can not find the logs and I do not know how to inspect it. driver r600 padeon HD7600