Low-res image scales when the slider is dragged.

[00-kat]

Video showcasing the bug:
https://github.com/upscayl/upscayl.github.io/assets/65649991/260d5142-8c5d-4b6d-a5a4-5ecea0b1fdcf

The image also doesn't line up after it is scaled.

[NayamAmarshe]

That's weird. It doesn't happen for me:

[00-kat]

I just tested on a Chromium browser and it works fine, so it's probably something Firefox-related (I'll try without any addons or similar in a minute).

Edit: the bug is still there even without any addons.