Ask HN: Why is there an option to deactivate Javascript in browsers?
What are the reasons someone would have their Javascript permanently disabled in a browser?
There is also an option to disable Images, why not CSS?
I still browse with JS disabled by default, however I turn on JS for the selected sites, only if I'd believe that they are worth it. Opera allows me to be selective, it has Javascript block configurable per site.
Why not CSS? Well, Opera can set a user css per site too. It's very convenient for some of the sites that are unreadable for me by default (i.e. small white letters on the black background or even picture background). It still can't explicitly disable HTML5 videos per site, AFAIK.
Javascript can be potentially harmful because it's code running on your system, albeit sandboxed to some degree. You can also embed code in images, but I don't think that's why people disable images. It's probably either because third-party sites can track your web usage through images or simply because they want a simpler browsing experience.
Also, there's the annoyance factor, just like with images. Back in the days, having ads, animated torches and sparkling mouse pointers disabled was a pretty good choice. Also: Popups and silly messages (alert("Welcome to my Site!") ridiculously common)
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