exec is currently only used by XFMG and only if FFmpeg integration is enabled, though we've added it as a core function in case we decide to use it for more things in the future.

proc_open is used by the email library so you will most likely want to address this or you may see issues with email sending.

exec and proc_open are often disabled for security reasons though really its usage can be safe and reasonable if used correctly. Generally we wouldn't recommend you ignore these warnings and instead you should look to re-enable these functions.