If you are using a web browser that supports webp, it can potentially improve load times by a lot, as webp is much more space/bandwidth efficient. I'm assuming this is why the instances are auto converting from other formats.
Because webp is a good format
It's converted to webp once uploaded on Lemmy. The BE supports it, but not every Lemmy instance is set up this way (though most are).
Is it a problem?
If you want to download or share it, it is
At least in jerboa when I download the image it gets saved as PNG. It could be that the web ui shows images as webp by default to make it faster or save resources
Why would they not be?
it's a png bro
Image downloaded as a webp. Encountered issue on firefox’s mobile app.
euphoria@kbin.social to 
Why the fuck is every post a .webp
If you are using a web browser that supports webp, it can potentially improve load times by a lot, as webp is much more space/bandwidth efficient. I'm assuming this is why the instances are auto converting from other formats.
Because webp is a good format
It's converted to webp once uploaded on Lemmy. The BE supports it, but not every Lemmy instance is set up this way (though most are).
Is it a problem?
If you want to download or share it, it is
At least in jerboa when I download the image it gets saved as PNG. It could be that the web ui shows images as webp by default to make it faster or save resources
Why would they not be?
it's a png bro
Image downloaded as a webp. Encountered issue on firefox’s mobile app.
I'm using Firefox mobile, works fine here
Your client is stupid
Image downloaded as a webp. Encountered issue on firefox's mobile app.