What version and browser are you using? This problem was already fixed in the latest version (5.5.4.4) on Chrome. For Firefox we’re working on making the new version of KR compliant with Firefox Web Store so it may take a while.
Chrome version 94.0.4606.61
The weirdest part is that using the example template (i.e;data.csv) seems to work smoothly, but using a csv that before never gave a problem is not working at all and shows:
[error] SyntaxError: Unexpected token N in JSON at position 0
So any help will be much appreciated as my intention is to go a step further and been able to automatized the gather of the data straight away to the csv. (ambitious I know).