> Does the corporate firewall block JavaScript? Because loads of them still do.
[citation needed]
> Does their ISP or mobile operator interfere with downloaded JavaScript? Sky accidentally block jQuery, Comcast insert ads into your script, and if you've never experienced this before, drive to an airport and use their wifi.
Ever heard of HTTPS?
> Do they have addons or plugins installed which inject script or alter the DOM in ways you didn't anticipate? There are thousands of browser extensions. Are you sure none interfere with your JS?
If the user installs an extension that breaks the web, it’s the user’s fault, and the developers should not cater to them.
[citation needed]
> Does their ISP or mobile operator interfere with downloaded JavaScript? Sky accidentally block jQuery, Comcast insert ads into your script, and if you've never experienced this before, drive to an airport and use their wifi.
Ever heard of HTTPS?
> Do they have addons or plugins installed which inject script or alter the DOM in ways you didn't anticipate? There are thousands of browser extensions. Are you sure none interfere with your JS?
If the user installs an extension that breaks the web, it’s the user’s fault, and the developers should not cater to them.