Click on the element to show a documentation for it:
Find usages of an element
Click on the element.
Choose Find usages from the pop-up window. All usages of that element will be listed in a separate tool window: You can navigate to each listing simply by clicking on it.
View usages diff
Click on the element.
Choose View usages diff from the pop-up window. All usages of that element in the file will be listed with an indication of which of them were added between the two revisions, which were removed and which weren't changed:
Go to declaration of an element
Click on the element.
Choose Go to declaration from the pop-up window. You'll be taken to a declaration of that element.
View hierarchy of an element
Click on the element.
Choose View hierarchy from the pop-up window. All ancestors and inheritors of that element will be listed in a separate tool window: You can navigate to each listing simply by clicking on it.
Highlight usages of an element
Click on the element.
Choose Highlight usages in file from the pop-up window. All occurrences of that element in the file will be highlighted: