The Expert view timeline sometimes zooms in if you drag a clip from Finder or the Project Assets panel to the Expert view timeline. The Expert view timeline can also zoom in if you drag the clip handles to trim a clip.
This behavior is most obvious when working with Adobe Premiere Elements on MacBook Pro with retina display.
Perform the following procedure:
Browse to the installation folder for Adobe Premiere Elements. Usually, it is at ../Application/Adobe Premiere Elements [Version]/Support Files.
Ctrl-click the Adobe Premiere Elements.app file, and choose Show Package Contents.
Go to Content/Frameworks and make a backup copy of the HandlerTimeline.Framework file at a different location on your computer.
Replace the HandlerTimeline.Framework file with the contents of the ZIP file you extracted earlier.
Restart Adobe Premiere Elements.
Expert view timeline zoom in, Drag clips, Retina Display, Mac Book Pro