[XMPPwocky]

"LibreJS is a good example in order to kill any potential Spectre/Meltdown attack. There is no attack when no code is being run."

If attackers who cannot add a comment to their exploit are in your threat model.

Personally, I've been using a browser extension that blocks JS unless it has a comment reading

> This code is NOT evil or malicious!

at the top. Haven't been hacked yet!