Here's some miscellaneous little stylesheet-related patches that might be worth applying to Wakaba and Kareha.

kareha/border-radius.patch and wakaba/border-radius.patch:

• Added standard CSS3 border-radius declarations to stylesheets using -moz-border-radius, since every common web browser (Firefox, Chrome, Safari, Opera, and even MSIE 9) now supports the standard declaration. Separate patches for Wakaba and Kareha included.

kareha/javascript.patch and wakaba/javascript.patch:

• Fixed set_cookie() to be RFC 2109 compliant. It wasn't escaping values before, so strictly-complying cookie implementations will choke on (for example) stylesheets with spaces in the titles.
• Behavior change to set the style cookie from within set_stylesheet(), instead of when the window is closed. This gets rid of inconsistencies when working in multiple tags; in particular, changing the style and then opening a new tab should ideally show the new tab with the newly selected style.
• Apparently MSIE 5 chokes and dies on regular expressions containing .*? or .+?. Not that I expect anyone to actually use IE5, but I tested the code with it and it didn't work, so there.
• (For Wakaba only) Cleaned up set_stylesheet().

kareha/pseud0ch.patch:

• Fix strange empty space between top of thread box and header text in Buun and Pseud0ch styles. I'm not sure why it had a 1em pad there.
• Adjust .replytext em selector to add underlining for <em> text, since the font-style: normal rendered it indistinguishable from normal text. (Was that intentional? Why?)

I tested these changes in Firefox, Chrome, Opera, and Internet Explorer, and everything appears to work.