Hello, Khaled.
I noticed a strange behavior when closing a desktop window in version 7.48 that did not present in 7.47.
First, activate the treebar, because it is easier to visualize what I will explain.
Now make active any window other than the Status Window. Example: a #channel
Open a @window desktop: /window -dC @test
Close the desktop window @test on [x]
Notice that the focus on the treebar goes to Windows Status and, in a fraction of a second, to the last active window.
Test these procedures in versions 7.47 and 7.48.
I did not notice any negative effect for mIRC with this situation, but only aesthetic.