Have been playing with SM for about four hours. Found SM compatible extensions for some of my "must haves", for other "must haves" used the converter recommended by mightyglydd successfully and in a couple of cases I found SM compatible alternatives. So far 16 work and only one is not working properly (Clippings).
I have also managed to place some of my tweaks in the userChrome.css file once identifying the proper "id".
At this point would say that SM is about 85% of where it needs to be to be equivalent to FF for my purposes. Also found a number of extensions I can live without.
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Let me think of how to structure it and what to call it. Also the thread you listed is this one (little confused). You are correct there may be others who are dreading the arrival of FF57.
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