[millisecond]

There’s also m.xkcd.com if you tire of hovers.

[gpvos]

Ooh, thanks; useful when I'm using my phone (as the m indicates, obvs), which truncates hover texts.

[saagarjha]

Early betas of iOS 13 actually used to do this and xkcd was explicitly brought up as a reason to not truncate ;)

[zzo38computer]

There is also explainxkcd, which displays the title text underneath the picture, and has categorization, searching, explanations (in case there is anything you forgot, or do not know, or just want to read other people's commentary), transcripts (helpful for search, and also to copy the text), and more.

Additionally, if you have user CSS in your browser, you can force it to display the title text even in the official xkcd web pages (CSS has a command to display the text of HTML attributes).