Web extension freemium business model

Hi friends!
I've released from some weeks this simple browser extension that will give to the user the ability to lock/unlock websites to avoid distraction while studying or working with the PC.

webLocker
Chrome version: https://chrome.google.com/webstore/detail/hdebdoonejiibceohcnbplnjelgelekk
Firefox version:
https://addons.mozilla.org/it/firefox/addon/weblocker/

At the moment this extension is an update of an old project that was locking only facebook and instagram and that I've launched about two months ago only on chrome. In these days I'm working to add some interesting features like the password protection for websites, an adblocker, a tracker blocker and a proxy to anonymize navigation.

I hope to implement these things in next major release the v.3.0.0 but before the update I want to develop a business model where the user need to pay to get all the features. I've noticed that the chrome web store has suspended the one time payments, this is a big problem to deal with for me, I don't know how to manage licensing and features unlocking due to the impossibility at the moment to purchase a dedicated domain to host a product page. I would appreciate to get some tips that can help me about this aspect, I want to growth the user base of the extension on chrome and start making money from licensing.

Definitively my ideal business model for this project will be the freemium but I'm not sure on how this can be profictable in short/long time. At the moment I'm feeling very unmotivated because I'm seeing users growing only on mozilla addons site but not on chrome. Some tips that can be helpful will be appreciated also about this aspect, I'm only a developer so marketing and other related stuff are not my main skills.

Thanks in advance for the replies