I experienced the exact same thing: I needed a web tool, and as far as I could tell from recent reviews, the offerings in the chrome extension store seemed either a little suspicious or broken, so I made my own extension in a little under an hour.

It used recent APIs and patterns that I didn't have to go read extensive docs for or do deep learning on. It has an acceptable test suite. The code was easy to read, and reasonable, and I know no one will ever flip it into ad-serving malware by surprise.

A big thing is just that the idea of creating a non-trivial tool is suddenly a valid answer to the question. Previously, I know would have had to spend a bunch of time reading docs, finding examples, etc., let alone the inevitable farting around with a minor side-quest because something wasn't working, or rethinking+reworking some design decision that on the whole wasn't that important. Instead, something popped into existence, mostly worked, and I could review and tweak it.

It's a little bit like jumping from a problem of "solve a polynomial" to one of "verify a solution for a polynomial".