Open_basedir (net::ERR_CONTENT_DECODING_FAILED)

When I enable open_basedir on an account using SMF forum, we are getting:

Error 330 (net::ERR_CONTENT_DECODING_FAILED): Unknown error.

The error disappears if I disabled open_basedir, but for obvious reasons I would like it ON

Anyone have any idea why this is happening?

Thanks in advance 😀