Browsers and the relative size of their default monospace fonts
One of the unusual things about Wandering Thoughts and all of my web stuff is that it's almost completely unstyled. In particular, I don't try to specify HTML fonts or HTML font sizes; I leave it entirely up to your browser, on the assumption that your browser knows more about good typography on your system than I do. However, this doesn't mean that my entries live in a pure world of semantic content, because in practice you can't divorce content from its presentation; how Wandering Thoughts looks affects what and how I write. One of the consequences of this is that I end up making some tacit assumptions about how browsers handle default fonts, assumptions that may no longer be correct (if they ever were).
Following a convention that I believe I coped from Unix manpages, I often write entries that intermix normal non-monospaced text with bits of monospaced text, which I use for a whole variety of things ranging from code snippets through Unix commands and filenames or just things I intend as literal text. This is a reasonably common convention in general, but when I use it I'm implicitly relying on browsers rendering normal text and monospaced text in something that is the same size or reasonably close to it. If a monospaced word is either tiny or gigantic compared to the normal text around it, the two no longer combine together well and any number of my entries are going to look weird (or be hard to read).
Unfortunately, it increasingly seems like browsers are not doing this and that they often have their default monospaced font be clearly smaller than their normal text font, sometimes noticeably so. This is of course platform dependent, and I think that common platforms still have the two fonts sufficiently close together in size that my entries don't look glaringly wrong. But I don't know how long that will last or how true it is for people who've tried to change their browser's default size (to make it either bigger or smaller).
If mixing normal text and monospaced text is increasingly risky, this is going to affect what I do here on Wandering Thoughts in some way or another. Most likely I will have to start moving away from mixing monospaced words into my regular paragraphs and confine them to their own out of line sections.
(This is a good part of why I care about Firefox's peculiar handling of font choice preferences. By default Firefox's monospaced font size is too small for me, especially once I adjust the size of its regular font.)
As a side note, this isn't just a browser issue, unless you take an expansive view of browsers. I also run into this in my syndication feed reader of choice, which of course also has to render HTML and also has to chose default sizes for normal and monospaced fonts. Compounding the issue, these programs often give you less control over fonts and HTML rendering in general than browsers do.