A number of people wrote in to alert me to the fact that Apple Mail fails to render last week’s HTML issue of TidBITS properly, instead displaying a tremendously long line length that requires expanding the window or scrolling horizontally. Feh!
The reason centers on the longest command line recipe in the article “Do Cool Things on the Command Line with Five Quick Recipes” (1 February 2016). Apparently, when a message contains text that uses the CODE tag in HTML, Mail sets its maximum line length based on the longest line. That decision seems like a mistake to me, but I’ll look into alternative ways to format what we call “code text,” or text that the user is supposed to type. It’s also possible that there’s a bug here that needs to be reported to Apple; Mail’s behavior in this situation is suboptimal, even if it’s not actively incorrect.
For now though, here’s a quick trick for how you can read any message that suffers from ludicrously long lines. With the message open, just choose Message > Send Again. That opens a new compose window showing the contents of the issue, with lines that wrap properly to the width of the window. When you’re done reading, close the window, navigate to your Drafts folder, and delete the draft you created. (Interestingly, the wrapping of the draft is wrong in Mail’s preview pane too; it’s correct only in the draft in its own window.)
Of course, there are plenty of other workarounds that might be appropriate for certain situations, such as selecting the entire contents of the TidBITS issue, copying, and pasting into a word processor. Using Send Again is simply the fastest way to get a readable display while staying within Mail.
I realize you may be seeing this solution too late to help for the malformed TidBITS issue, but file it away in your head in case you run across this problem again.