Force/encourage categorisation of unrecognised transactions

[floehopper]

I've caught myself clicking the Chrome extension button, discovering that the Chrome extension doesn't know how to categorise the transaction, but then only filling in the description and not noticing that the category defaults to the category used to explain the last transaction.

It would be nice if the Chrome extension could set the category to blank (adding such an option if it doesn't already exist) to force us to explicitly choose the category. Alternatively making it much more obvious if the transaction cannot be explained.