Hello everyone and thanks for all your work!

I have some fixes to the xwidget code that I'd like to contribute.

These should achieve three things

1) fix `xwidget-webkit-current-url' in xwidget.el so that it actually displays the current URL

2) fix the Objective-C code in nsxwidget.m to eliminate memory leaks

3) implement the function `xwidget-webkit-estimated-load-progress' in Objective-C, making this functionality available for macOS as well

Regarding 2), I have tested my changes with the Instruments app within the XCode dev tools. I was able to test them on two different machines: a MacBook Air M2 running macOS Ventura 13, and an Intel processor running macOS Big Sur 11.6.7.

When testing with Instruments, it appears that Emacs isn't leaking memory anymore. I am still seeing some leaks, but according to Instruments, the responsible libraries are system libraries, and not Emacs itself.

If possible, I would appreciate it if other people can test/profile these changes as well, and share their feedback.

Assuming the changes are correct and accepted, would it be possible to include them in the upcoming Emacs 29.1 release?

Technically, none of these are new features; it's just fixes to existing features.

I intend to keep working on xwidget support for macOS (fixing remaining issues and implementing missing functionalities), but I'm not sure when I'll be able to get to it; for now I'd like to start by contributing these first major fixes.

Thanks in advance for your feedback; let me know if you need anything else from me.

Best,

Andrew