Subject: Re: bug#59828: Fundamental Mode buffers fail to keep text properties

From: Yuan Fu <[email-masked]>
Date: Mon, 5 Dec 2022 21:41:23 -0800

>>> 
>>> Just to clarify:
>>> 
>>> 1. If font-lock-mode is off, you should use (propertize … ‘face …)
>>> 2. If font-lock-mode is on, you should use (propertize … ‘font-lock-face …)
> 
> If I have a function that does the inserts, should I include the two different conditions, 
> whether "font-lock-mode" in "off" or "on" ?
> 
> Test whether font-lock-mode is off, then use (propertize … ‘face …)
> Test whether font-lock-mode is on, then use (propertize … ‘font-lock-face …)

It depends on your use-case. If you want to be safe you can just apply both properties, then it will work no matter font-lock-mode is on or not.

Yuan