This function has been marked as obsolete. In Qt 6.0 it's removed
entirely, so we must use getContentsMargin() explicitly instead
(margin() would do this for us).
Ditto for setMargin(), in which case we use setContentsMargin instead.
setMargin() would just pass its argument to all four parameters of
setContentsMargin(), so we can do the same.
Most settings which affect determinism will now be synced on NetPlay.
Additionally, there's a strict sync mode which will sync various
enhancements to prevent desync in games that use EFB reads.
This also adds a check for all players having the IPL.bin file, and
doesn't load it for anyone if someone is missing it. This prevents
desyncs caused by mismatched system fonts.
Additionally, the NetPlay window was getting too wide with checkboxes,
so FlowLayout has been introduced to make the checkboxes take up
multiple rows dynamically. However, there's some minor vertical
centering issues I haven't been able to solve, but it's better than a
ridiculously wide window.
