Same problem here. The expected user behaviour would be to either not convert the image to base64 encoding, but save it like with the attach feature or wp editor in the backend, or disable the option that allows pasting of images into the wp editor field.
ad 1. Pasting the image directly into the post:
What I really do not get is that you already have that working here in your forum software. Is it really so hard to implement the same function in the comments?
ad 2. Incompatibility with Litespeed server:
I will contact Litespeed but I doubt they will change their server software just because a plugin doesn't work. I never had a problem with uploading images with any other plugin and I tried a lot of them.
Copying and pasting an image into the comment works like a charm here in your forum, but as @ventilator reported and we experience as well, it outputs garbage in WpDiscuz (with the Media premium plugin).
So we'd like to either have it working, or not have copy-paste images supported if it's not going to work as expected.