[mythtv] Preview images from a bookmark

[Otto Kolsi]

I have a slow backend and I've disabled the live preview of recordings. 
I have "Generate thumbnail preview images of recordings" setting enabled 
  and "Generate preview image from a bookmark if possible" disabled.

If I understand these correctly, Myth should not create new preview 
image from the bookmark because I have it explicitly disabled? With SVN 
9645, the preview image is being updated every time after making a 
bookmark and exiting from the playback back to recordings.

This is mainly cosmetic issue, but because of the slow backend, each 
preview creation takes 1-3 seconds. And during that time frontend stops 
responding or slows down.

Is this a bug or have I misunderstood the settings?
-- 
   Otto