Re: Removing the `window-id' frame parameter on non-Core Input platforms

[Po Lu]

Note that the problem this is supposed to fix is specific to a single
version of a single window manager, so I installed an entry in
etc/PROBLEMS instead, but this could still be a valid concern if the
problem resurfaces in the future

Eli Zaretskii <eliz@gnu.org> writes:

> Please describe the problems you see in continuing the support for
> window-id.  You say it's unreasonable, but please tell more to clarify
> why it is so.

Essentially, to work around the freeze described in PROBLEMS, a frame's
window is recreated which changes the XID of the frame.  Non-Emacs X
clients that have kept track of the previous XID will crash with a
BadValue error when trying to use the previous XID.

Other uses of the `window-id' parameter such as to display windows as
children of a frame are discouraged on XInput2 builds, as it can
interfere with XInput2 event handling (but this is a theoretical
problem, I have yet to see it happen in practice to Emacs) in
complicated ways, such as unexpected touch sequence ownership changes
leading to Emacs crashes.

Thanks.