Uncommon monetisation way for freeware product

Hi,

Years ago I made a side project called CRXExtractor. It is a free browser-only tool that serves very simple need - he extracts a source code out of Chrome Extension package (.crx file). I don't believe anyone ever would pay for it, and being zero-price for everyone looks like a good fit.

Currently I monetise the product with Google AdSense, but the most of time ads being shown are very irrelevant. Also, I don't have HQ 10k+ DAU to go with Carbon Ads or another premium ad network.

What other options do I have to monetize it? Ideas?
Thanks in advance, Indie Hackers!