There's probably a line of code that looks like this: > echo('<html dir="$dir" lang="$lang">') (or something similar), and they unconditionally include the `d

There's probably a line of code that looks like this: > echo('<html dir="$dir" lang="$lang">') (or something similar), and they unconditionally include the `dir` attribute without checking if it's already set to the default value a browser would assume.