Via the Steam Community:

MISC

• Mitigated a performance issue that primarily affected Windows 10 users with recent Intel CPUs.
• Fixed a case where the Delete Item inventory option wasn't working.
• Fixed a case of visual corruption using iron sights on AMD GPUs.
• Expanding list of console variables addons are allowed to change.

MAPS

Overpass

• Fixed the Party balloons.

Rumor has it:

• Size is close to 525 MB (with Workshop Tools installed)