Just use this https://archive.is/ seems to work fairly well and however it's crawling the sites bypasses paywalls... at least for me.
Can we throw twitter links in that bucket too?
The popular alternative (many paywalled articles will even have a top comment with this generated already) is to use the fabulous service https://archive.ph
If you look at the comments there will usually be someone who has posted a link to an archive that bypasses paywalls.
But no, I haven't seen any existing extensions or userscripts for it
This extension will auto-bypass many paywalls: https://github.com/iamadamdev/bypass-paywalls-chrome
I'd love to see auto pinning of comments which post a paywall bypass link
This previous discussion may assist. https://news.ycombinator.com/item?id=26212645