JavaScript blocker guide?

I red that to set JavaScript blocker properly I need a lot of knowledge. Where I find good guide for this?
Also, how I know which scripts to enable. If I enter website and even block 4/6 javascripts, how I know 2/6 ones are safe (and 2 last ones are required for page to work)?

How to surf the web with js on without with safety? Virtual Machine?

Nope! just use Noscript addon

Testing! but ofc if you on website like news do not open that little js that related to or so use your brain

It will kinda work but if you want more you can use tails or something similar

Does a website use to much Javascript? A good test is seeing if you can read that website in w3m or similar software. if it doesn’t render, than it’s a good guess there is way to much javascript in operation.

Use the desktop when possible, and on desktop the mobile site. I’ve found that I can use twitter in w3m using the mobile website.

I’m not sure if that’s because they don’t often use javascript, or what.

Check out The Hated One tutorials, he has made some for uMatrix, uBlock Origin, No Script and some more which are unrelated to script blocking. My recommendation is to use uMatrix and uBlock Origin, uM will tell you which scripts are 1st party and which 3rd party, this can give you an idea of which you should block. Also, uM gives you more granular control and can know the difference between a 3rd party script of FB on another website and the same script as a 1st party one inside the FB website, thing that NS don’t.
I recommend you to use the reading tool which Firefox provides, a lot of times you can read a blog, article, etc without even having to activate anything.

What is a name of reading tool? There are only not supported ones in mozila adons.

You suggested Tails, but if I run Java Script on Tails, it can still read some of my hardware paramenters (graphics card etc.)?