It is not clear what happens to the window transparency after the last update. Even so, it is understandable, but it causes confusion and irritation.
For the first, it is not clear why it was necessary to “improve” and break what already works properly. All windows were opaque by default. I have had to do just one mouse click on the icon in a window’s/group of windows title to make it transparent. And there were no need to resize it for this.
For the second, after your update, opening each new tab in the Channels (chats) window makes the entire group transparent.
Despite the fact that the transparency in my settings is set to 18%! And it happens every time. I need to expand manually the window so that the part of its title without channel tabs can be visible, make it opaque and return the window to its initial size.
Thus, what we had: with just one and single mouse click we could make any window/group of windows transparent /opaque.
What we have after the “improvement”: we need to expand the Channels’ window each time to get the part of its title free of any tabs in order to call up a context menu. And now you need three movements (instead of one) to turn off the transparency (call up a context menu, select a command and mouse click). And then return the window to its initial size. These context menus are so annoying, and you add them more.
Remove at least the default transparency of any new window.