I cannot change the font size of package explorer in Eclipse

Question

I try to change the font size of package explorer in Eclipse from menu Window → Preferences → General → Appearance, and I fail to change

Answer 1

FYI:

From Eclipse v4.4 (Luna):

It looks like the CSS files are no longer in the old folder:

`eclipse/plugins/org.eclipse.platform_4.x.x.vy/css`,

They are moved to the new folder:

eclipse/plugins/org.eclipse.ui.themes_x.x.x.vxxxxx/css

And you must select a theme to apply it, in the menu Windows → Preference → General → Appearance.