Changing gain in the audio file editor window

In L9 in the audio editor window you could just select a part of audio that was too loud or too quiet go to gain and make it softer or louder.

I can't seem to find this feature in LX. From this video

Its done in the track.

But in this video the audio editor window has three tabs

Track, File and File tempo

In my project the File tab is missing although it's an audio file. Why?

thanks

This is my situation in the audio editor