I took the title of this thread to mean that you wanted to count the words in the current selection, but the script counts the number of occurrences of selected text throughout the entire document. Just pointing out the difference in my interpretation in case any future readers do the same.

I continued with my search and was able to use the below snippet and copied directly into startup.py script. I also set initialization to ATSTARTUP to automatically load this python script. I am not sure if its elegant, but it works

def callback_sci_UPDATEUI(args):
        if args['updated'] & UPDATE.SELECTION:
            matches = []
            if editor.getTextLength() < 100000:  # don't search "big" files
                if editor.getSelections() == 1 and not editor.getSelectionEmpty():
                    try:
                        editor.research(r'\Q' + editor.getSelText() + r'\E', lambda m: matches.append(1))
                    except:
                        matches = []
            l = len(matches)
            notepad.setStatusBar(STATUSBARSECTION.DOCTYPE, ' ' if l == 0 else '{} occurrence(s) of selected text'.format(l))
editor.callback(callback_sci_UPDATEUI, [SCINTILLANOTIFICATION.UPDATEUI])

we still will likely forget the occasional import in the example scripts.)

Lately I’ve been testing any scripts I post here in a fresh-portable-plus-Pythonscript extract. It helps to point out such missing things.

@Neil-Schipper is right on. Looking at Scott’s script from that old discussion, it is using the re object, so the script definitely requires import re

Many of the regulars here have customized their PythonScript startup.py to automatically import certain libraries, like import sys and import re, which means that we don’t have to have them in all of our individual scripts… but then we forget when publishing an individual script to help a user that they won’t necessarily have those already imported. I think we’ve gotten better at remembering those imports over time, but four years ago was before some of those lessons-learned were taken to heart. (And since we’re human, we still will likely forget the occasional import in the example scripts.)