[watwut]

Compilation of everything, how it shows compile errors and warnings. I see them in tree, in list, easily and quickly all of them. All of them for whole project at once and trustworthy. Less bogus warnings and contraproductive suggestions.

I never needed to fiddle with "command line shortener" ridiculousness in Eclipse.

Better code navigation and discovery. Eclipse always finds everything, every called and callee to depth. Same with inheritance. Even where Idea has same views, for some reason they hide it and only former Eclipse users stumble on it.

Actually safe refactorings. Idea occasionally "refactors" by creating bugs.

I had some cases where Idea simply formats code wrong. And it was impossible to configure to formát it right.

Also, Eclipse compile by default. It is ridiculous to have to remember to press shortcut to compile in modern IDE. I know it is configurable, but still ridiculous default.

Square selection.