Lazy loading could also be made as a user option in a web browser, too. (An implementation could also have an option to only use lazy loading if the dimensions

Lazy loading could also be made as a user option in a web browser, too. (An implementation could also have an option to only use lazy loading if the dimensions of the picture are known.) "Make the image bigger when you click on it" also can be done without JavaScripts, in a few ways: One way is to just use a ordinary hyperlink directly to the image (and optionally you can override it if JavaScripts are enabled), another way is to just to use features that the web browser might have (if the user has them, they can be used; if not, then not), and a third way might be to use CSS (although I generally want to avoid CSS requirements, too). Fade-in effects can also be done using CSS, but may be undesirable (I am one who would prefer to reduce animation as much as possible, and other users too). For JS based search functions with JSON, you could do something that I mentioned before which is <link rel="data"> and the user can make their own search functions if wanted (maybe a browser or extension might have a JSON searching function with many options (that the web page might not necessarily implement; I do often find wanted to make queries that the web page does not implement)), but if JavaScripts are enabled then it will use that one. Even if the data is rendered into HTML in server-side scripts or generated static pages, you can still have <link rel="data"> or <a rel="data"> to allow to access the raw data, too, since it will sometimes be useful. But in any case, you should almost always ensure that it works properly with JavaScripts disabled, and usually should work with CSS disabled too. Use <noscript> blocks if needed, and include API documentation or download links or whatever, not simply "This requires JavaScripts to work". For some types of web apps (e.g. interactive games), it might require JavaScripts but even then you can include links to documentation, and if it is open-source also source codes, even if scripts are disabled. In general, in my opinion, most web pages should need neither JavaScripts nor CSS (and often does not need pictures either).