Yes it stops at 800px by default. Longer lines would be insane… I find comments on your blog slightly hard to read though, especially with the short line-height for the font size you have, in addition to the white lettering on a black background, which is already challenging. A narrow leading with long lines and no sufficient margins is generally not very friendly to the eye.
I hope it does :) I have been working hard on the heavy css code, which is btw a repeat of the same code 3 times in the same file (big screw-up from IDC there).
A full 740px width might too large in my view for comments. i.e. It can get hard to read from left to right. I don't foresee endless threads requiring so. I would say if it gets too narrow it may be time to stop being too argumentative. ;)
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