Some bugs I've noticed:
convert... webp --- Settings..., nothing happens when you press this button. Also if you choose from drop down menu anything else and then return to webp it will be grayed out.
With webp it is better to think 2 things, lossy and lossless. I don't know the lossy so well as I jumped directly to avif/jxl but webp lossless is amazing. It is making PNG completely obsolete, makes virtually always files 50% smaller, sometimes up to 90% smaller. And is starting to be almost as compatible.
The only place where you would still need PNG is with 16bit lossless images as webp do not support them and jxl support is not yet wide enough.
Of course JXL lossless is the best lossless compression algorithm so it would be cool to get it here as well but maybe webp lossless is a bit higher priority (in certain types of pics lossless webp beats even lossless jxl)
Bug report, WEBP, AVIF, etc.. settings
Moderators: helmut, XnTriq, xnview
Re: Bug report, WEBP, AVIF, etc.. settings
One more lately observation.
Although lossless webp and lossless jxl often create same filesizes there is huge difference in computational complexity between them (at least according to my couple of tests)
Lossless encoding speed of test file:
webp lossless 6 secs
png 3 secs
jxl lossless 2.3 secs
In other words for archival purpose of lossless files lossless JXL seems to be best. Sometimes webp does create even smaller files (depending on content) so it is good to have both options.