I came to know that I can add content editor web part in SharePoint page and add javascript code to it. For a specific purpose, I needed to add a web part in a list’s Edit form.
I made sure that I set up Launch from Dialog to No as shown below:
And then opened the Edit form in IE 11 and tried to do Settings > Edit Page as shown below:
But nothing happened.
Then I tried the same thing in Chrome and it worked just fine.