maximum size for file to generate thumbnails is 32768Kb

[kentzversky]

Edit>Preferences>Display>Do not generate thumbnails for files exceeding this size: 32768 Kb.

If u set bigger value and return to this menu later it still on 32768.

Because of this thumbnails for big video files are impossible.

Source code editing solution found by me:
http://relict.blogspot.ru/2013/01/thumbnails-in-pcmanfm.html

but better idea would setting this value to zero disables file size limit for thumbnailing (thumbnail all)

[LStranger (andrej-rep)]

It cannot be. That setting affects only internal image thumbnails loader. I have all my video files thumbnailed as a fact, and my limit is set to 2048K.

And as for setting it 0 - it works exactly that way, unlimited when set to 0.