I am afraid that I have also found that Enlightenment should also be listed as a desktop that requires the LibAppIndicator3
Don't be afraid. Just add it into your coming patch.
I am not sure what patches look like at the moment, Alex's suggestion is dependent on a separate patch providing a function to read the proc filesystem, complicationing the issue a bit. I would consider Juha r62020 best bet but it need another line referring to Enlightenment.
No, Alex's suggestion does not complicate anything because it is not applied to trunk or anywhere. He is working on non-issues or "nothing-burgers" as Americans say, which is a little irritating when there are so many open bugs.
Why would you
consider r62020 the best bet? Just do your changes in trunk. It
always has the latest sources. Yes, r62020 is the latest revision regarding unitywsctrls.pas but that is kind of irrelevant.
You are using SVN trunk now, aren't you?
What is the best approach ? A new patch assuming r62020 is applied ...
Assuming ... WTF! r62020 is already applied, that is why it has a revision number. It will even be merged to the fixes_2_0 branch.
... or a modified patch that extends 662020 ?
That is
far far future, maybe in year 22019.
BTW, your environment variable LAZUSEAPPIND sounds like a good idea. If not found, the behavior would revert to what it does currently, thus making the change backwards compatible.