The name of the file is "20000716.gif", which I am guessing is the publication date of 16 July 2000. Reverse-searching the image gives no results, and the original website is probably long gone (but could be archived - no way to know without knowing what it was). I've showed this image around and also posted it on TOMT today, but no one has recognised it so far.
Here's all the context I remember: The blue guy, who I think had a friend who is not in this strip, was imprisoned in a dungeon and has met the human character there (who was also chained up and I think is wearing some sort of disguise here). The red M&M was not a regular character, but was implied to be there just out-of-frame in an earlier strip and shows up here as a "deus ex machina" gag.
No clue about the characters' names, or anything else that would make searching for it feasible. It's been 20 years and the image is all I have.
Like you mentioned, the link in your image actually gives some solid hints to where we can look for this webcomic and find more info. Simplifying the link of the .gif you provided takes us to 'Tails of Lanschilandia' which has a number of still-updating comics. Good chance that whoever made your mystery webcomic is still making webcomics here!
The website's archives only seem to show pages/panels later than 2012/2014 (as do most of the artist's online presence) so going off of the 07/16/2000 date or similar artworks will prove to be difficult. You could also try to contact that artist directly through their contact info on the site (they do seem to be fairly active on DeviantArt and Twitter); if they are hosting this on their site somewhere they may know where it came from (or as I said probably even made it).
The other part of your link's url 'chickenbagpipes' wasn't giving me any immediate answers and wasn't tied to any existing comics by the artist, but if it rings any bells may clue into somewhere else to investigate. Best of luck!
Edit: Based on the username you are the artist on the site I kept referencing - in which case this info is probably not relevant! My mistake and Apologies if that is the case, I didn't read carefully enough!
Yeah, I uploaded it to my own webspace to share, which also has my webcomic on it - sorry for the confusion!
I don't have any clues as to what the original URL or website name was. The file was in a generic download folder on my harddrive and the filename is seemingly just a date. Nothing really helpful there. :<
Tried to use Google lens. No luck. This was probably a comic by some random guy on an art site and he/she randomly deleted his/her account. Happens. A lot of web art from that time is lost. I used to watch an artist called Kalma the Hedgehog, then suddenly they got rid of a bunch of their art and never reuploaded it. It's a shame, but that's the nature of the internet.
Have you tried looking through the bad webcomics wiki? I'm assuming they're still around? This looks like something they would have written a review on.