Flashpals on screenshots

See merge request STJr/SRB2!492

Fix SIGSEGV from sending lindefs/sidedefs in savegame due to duplicated lines.

See merge request STJr/SRB2!490

Set modifiers in a non-reactive manner

See merge request STJr/SRB2!456

Don't skip frames when connecting or paused

See merge request STJr/SRB2!489

This reverts commit 7ac0a8b4.

Alias recursion hotfix 2

See merge request STJr/SRB2!482

Fix music load lag by reverting tag changes

See merge request STJr/SRB2!486

Ban IP command

See merge request STJr/SRB2!460

Don't count down wait timer when executing a command line

See merge request STJr/SRB2!483

OpenGL Sprite Billboarding

See merge request STJr/SRB2!485

add parentheses around these conditions to fix sloped lights cutting out lights on FOF walls for apparently no reason

not making a merge request because this is so laughably stupidly simple

Don't enable UPnP support if NONET is defined.

See merge request STJr/SRB2!484

Because songs without this tag will skiplag when loading.

1. It's slow, 2. It's incorrect

Should work on both normal and precipitation sprites.
Sprites that are split by lighting should work correctly.

Detect infinite alias self-recursion mixed with other commands, such as in the case of `alias a "echo test; a"; a`.

(Unfortunately, this does not work if "wait" is used instead of "echo", but oh well)

Console quality of life changes

See merge request STJr/SRB2!479

Keep console open in certain instances

See merge request STJr/SRB2!480