I've never seen any clear documentation from IBM on what is allowed and where. In a majority of places, I consider this unsupported and subject to removal. In Maximo, you can apply CSS classes (including with things like conditional UI) to controls which is supported. You can also use rich text controls which display a variety of HTML tags and is supported.
But other times where users have been able to enter HTML (like your description example) IBM has made an effort to suppress like (
IJ23871: HTML TAGS CAN BE INPUTTED INTO FIELDS WITHIN MAXIMO (ibm.com)). So while something may work today, I would not assume it would work tomorrow.
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Steven Shull
Director of Development
Projetech Inc
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