I'd suggest opening the browser dev tool and going to the network tab. then start typing really fast in one of those areas. this lets you visually see if a bunch of queries are being triggered while typing (typing faster would be more queries ran, slowing down the web app).
did you try OPs solution from 'EDIT2'? he changed the event handler to "Blur" insted of "Change", reducing the number of times the query gets called.
For example, a text input which updates on every user input might use an expensive underlying query. Instead of calling this query on every keystroke, use Debounce to run the query only when the user stops typing.
@seb @whynot
you could also try using debounce. it will let the first call to run the query run immediately then pause for the specified ms before letting the query fire again. doing it this way, you can still update the source while the user types just not as often (and in reality, there's no real need to update the source after every key press)
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