Cannot highlight all occurrences of a selected word in Eclipse

Question

I tried using the Toggle mark occurrences (Alt + Shift + O) button and also in Preferences -> General -> Editors -> Text Editor -> Annotations

Answer 1

The standard "Mark Occurrences" functionality included in Eclipse that everyone recommends only highlights identifiers in editors of whatever language. For example, it won't highlight int in C editors, and it won't help at all in the Console pane.

So if you want to highlight ALL occurrences on ANY word in ANY Eclipse pane (kinda like Notepad++ does), try the Glance plug-in for Eclipse.

As of November 2017 Glance works for Eclipse Neon and Oxygen. There was a period of time in which Neon was unsupported, and a fork appeared, but it seems unnecessary now (and abandoned).