I am not an expert on font-lock though, so this patch might not be
correct.  <excuses>Also, since I'm on a laptop running on battery
power, I don't intend to run make check right now.</excuses>  I am
sharing this patch in case someone well-versed in font-lock finds it
"obviously correct".

If that is the case, I have two more questions for additional patches:

1. Would it make sense to stuff most of these two functions's code
   into a third function called e.g.

        font-lock--add-text-property (start end prop value object append)

   in order to reduce duplication?

2. I guess some new automated tests would be appreciated?


Thank you for your time.

Kévin


[1]: http://lists.gnu.org/archive/html/emacs-orgmode/2019-04/msg00101.html
[2]: http://lists.gnu.org/archive/html/help-gnu-emacs/2019-04/msg00240.html



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