Announce Lists Changing Spaces to Tabs?

Greetings! I’ve been trying to send an announcement that is preformatted plain text (e.g., not HTML). As such, there are leading spaces at the start of several lines.

Every time I post this text, however, the announcement appears to go out with the spaces converted to a mix of tabs and spaces (basically tabs, but depending on the # of spaces there are leftovers).

I’ve tried posting via Safari and Firefox (MacOS). The text is absolutely devoid of tabs. Any idea what might be happening? As it is, announce lists are useless (formatting-wise) in plain text mode. Clues welcome and appreciated!

  • Joe