How do you force spaces preview to always use a picture in El Capitan?

Since upgrading to El Capitan my spaces previews sometimes are text only, and sometimes are full image previews. It seems to be related to whether or not I initiate Mission Control on a space that is fullscreened or not.

Is there a way to force spaces to always use a preview picture?

Desired:

Sometimes occurring:

Solution 1:

My two-part solution leverages Better Touch Tool + FunctionFlip:

Part 1 - Trackpad:

1) Go to system prefs -> trackpad -> more gestures -> uncheck mission control (effectively disabling the mission control gesture if it was enabled).

2) Download and install Better Touch Tool, open it, and go to trackpads to set up a gesture rule that uses the mission control + immediate preview action they made especially for all unhappy people (means no mouse hacks needed as mentioned in a previous answer). Don't forget to go to basic settings and set BTT to launch on startup as well. Here's a screenshot:

Part 2 - Keyboard

(assumes you already have BTT installed:

1) Download and install FunctionFlip, enable it in accessibility, then open system prefs - function flip - check F3, click the "start FunctionFlip" button, check the "start functionflip at startup" checkbox.

2) Go to BTT - keyboard - make a new keyboard shortcut using your now specially exposed F3 key and the same "mission control & immediately show desktop preview" option used in Part 1 above.

Hope this helps!