Ark

I just set up a Wine environment and installed 3.1.0 there. Looks fine, still not able to replicate.

Actually, I do not know what it is like to program in Python on Windows (also considering dependency issues and all), and I do not have a Windows machine available for testing, but I guess it would be far from simple, which is why I am sorry for having bothered you. I wonder whether there is another way to replicate this issue.

Thank you for all the information. Let me summarize: Windows, version 2.0.0 or higher (version 3.1.0 also affected, but version 1.2.1 works fine), probably specific to the magnifying glass, probably unrelated to DPI issues, probably unrelated to the image format, not just animation rendering artifacts or anything similar. (Note to self: I just tested with GDK_SCALE=3 which does show yet another bug, but at the same time, it demonstrates that the flickering issue is unrelated.) Is it possible for...

Could you please try different values for "animation mode" (see Preferences→Advanced)? Do they have an influence? If that did not help: A lot happened between 1.2 and 3.1.0, so we might need to find the first version that introduces the issue. Could you please try 2.0.0? I suspect it to be a GTK+ 3 thing which MComix uses since 2.0.0. Another thing that might have an influence here, at least on Windows, is display DPI scaling. Could you please try different settings there? (You might want to note...

Thanks for the info. If the issue persists even when using the L key instead of the middle mouse button, it probably means that it is not directly related to the middle mouse button malfunctioning or anything like that. Maybe something with the mouse cursor somehow disappearing and reappearing for some reason. I wonder whether it has something to do with display DPI. Anybody here who knows whether GTK3 has its own notion of display DPI such that it might conflict with Windows' notion of display DPI?...

Thank you for reporting a potential bug. Do you hold down the middle mouse button to activate the magnifying glass? Or do you press the L key to turn it on and off? Does it make any difference with respect to that strange behavior? Do you notice any differences between different moving speeds? If you move very, very slowly, will the magnifiying glass always eventually be rendered? Or are there cases where the mouse cursor arrives at a new position, you stay at that position, but no matter how long...

Looks good to me. Merged. Thank you for your contribution.

Eliminate deprecated Gtk.VBox and Gtk.HBox