Anything in a PlainText card that looks like an HTML tag is stripped not escaped

I can't create any PlainText cards that contain a less-than sign, a word of text, and a greater-than sign without it being mistaken for an HTML tag and stripped from the saved card.  When that happens, the text so stripped is simply no longer there to edit and maybe work around.  This makes sharing shell scripts, manpages, and snippets of the same impossible as cut-n-paste plain text.

I can't give an example here or share a screenshot of the resulting card because it would only manifest as empty gaps one space wide.  The screenshot I am sharing is of the plain text in the XFE text editor that I pasted verbatim into a new PlainText card (called xmount on my wagn): The word "string" and the punctuation surrounding it simply vanishes as if it was an HTML tag.

Version 1.18.6.