From what I understand these shadows concern among others those of pop-up and drop-down menus? I don't know if I'd appreciate those becoming 5x smaller in my own theme setting. I'll try on my end but could you post screenshots before and after too, please?

Making this an option will not be that hard, it will just require copying the value from the regular opts struct to a variable in the shared library. The simplest way would be to have a global variable in x11helpers.cpp, with a setter function that gets called with the value read from the config file or the config dialog.

It may actually be more complicated to change the value at runtime, the code doesn't seem to written with that possibility in mind.

Another thing: Yichao, do you know it this shadow size value has an equivalent for non-X11 implementations?

In D5909#110676, @yuyichao wrote:

So I'm certainly fine with an option (passed in as a parameter to X11Init functions)

A parameter to X11Init means the effect of changes cannot be evaluated without restarting the application. Also, those functions are called before the configuration is read from file.

I'll have a look.

Here's a draft implementation to put this property under user control. I've put it in the Advanced section, but wasn't sure exactly how to call the control if the parameter doesn't represent the exact size (= I've also left out the unit).

Done only for Qt5, Qt4 and GTk will follow when/if this is acceptable.

Nice fix. Thanks

I think the name is fine. It's still the "size" . It's a gradient that fades away with the end being at this many pixels away.

You're welcome. Maybe I'll "commandeer" this revision from you then, unless you feel like doing the copy/pasting to Qt4 and GTk yourself? ;)

looks good to me