The latest beta v7.69.175 can be downloaded here and includes the following changes:

Beta v7.69.175 changes:
1.Item 1, fixed. Now uses LOAD_LIBRARY_SEARCH_SYSTEM32 or
  LOAD_WITH_ALTERED_SEARCH_PATH to force use of Windows system folder.
  Tested under XP, 7, 10, 11.
2.Item 2, added.
3.Item 3, added.
4.Item 4, added.
5.Item 5, fixed
6.Item 6, added.
7.Item 7, fixed.
8.Item 8, changed.
9.Item 9, fixed.
10.Item 10, fixed
11.Item 11, changed.
12.Item 12, extended
   while maintaining backward compatibility.

1.Changed the way Windows system libraries are loaded to prevent DLL
2.Added extra format check to channels.ini [recent] items to split
  at commas in case of invalid format.
3.Added tray tip warning on startup if mIRC has been minimized to the
  system tray but Windows has hidden its icon.
4.Added /socklisten -n switch to disable Nagle algorithm on socket.
5.Fixed /socklisten -pu with UPnP, IPv6 address, and dual stack
  not opening an IPv4 UPnP port on the router.
6.Added /drawsave -a [x y w h] <filename> switch to allow specifying
  area of bitmap to save.
7.Fixed Aero theme bug where if /window +b was used, a miniature
  titlebar was being drawn.
8.Changed the way installer updates servers.ini and channels.ini so
  that only the servers.ini [servers] and [networks] sections are
  updated, and only the channels.ini [channels] section is updated,
  preserving [recent] and other sections in the files.
9.Fixed IPv6 addresses in server list not being saved correctly.
10.Fixed colons being stripped out of nick, alternative nick, user,
   emails, /nick, and server list entries.
11.Changed "set as default" option in font dialog so that it is checked
   by default when disabled for some types of windows.
12.Extended $mouse.key to detect different combinations of left/right
   key presses.