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

[Yuan Fu]

> On Dec 4, 2022, at 10:30 PM, Heime via Bug reports for GNU Emacs, the Swiss 
> army knife of text editors <bug-gnu-emacs@gnu.org> wrote:
> 
> 
> Have noticed that when I insert text with colour properties in a buffer
> using fundamental-mode, the text properties (e.g. colours) get lost.

I assume you used the ‘face property, right? If you replace ‘face with 
'font-lock-face, does it work?

Yuan