I have to work with text file where block delimiter is more than 1 empty lines.
You need to alter the file to make it amenable to TM's folding scheme:
One solution is to do a find and replace on "\n\n",replacing with something like "end\n" or your choice of marker (closing bracket, a symbol like or whatever else unique which appeals to you)
That makes the file easy to read, and easy to write a fold for.
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