Viewport Flickers when opening a Blueprint and Setting it as a Docked Tab on El Capitan

When docking a blueprint as a tab in the main viewport the sprites and other actors placed in the default scene (including player start) begin to flicker.

This flicker persists until you close and re-open the project. This issue is a bit odd because it only seems to occur on El Capitan, and sometimes won't appear after following the repro steps. I had another team member test on his Mac with OS X Yosemite and the issue did not appear.

The user reporting the issue mentions it will show up eventually the longer you have the editor open.

Regression
Yes. This flickering behaviour was not apparent in 4.10.4.

Most successful repro
1. Create a new blank blueprint project.
2. Create a new actor blueprint.
3. Open the actor blueprint and set it to be a full docked window next to the viewport. Use the attached image for reference.
4. Click back on the viewport tab.

Outcome The player start and other objects placed in default scene begin flickering.

Expected Nothing on the screen flickers

Tested and reproduced 3/5 times