Gettin a java.lang.NullPointerException when opening the marketplace in Eclipse Mars 4.5.2 under Linux?

org.eclipse.e4.core.di.InjectionException: java.lang.NullPointerException
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:68)
	...
Caused by: java.lang.NullPointerException
	at org.eclipse.swt.widgets.TabFolder.gtk_switch_page(TabFolder.java:570)

Try forcing eclipse to no use gtk3:

export SWT_GTK3=0
eclipse