Fedora GNU/Linux 64 bit v 21/ intel cpu / nvidia gpu
Broken: Current Master
Short description of error
Some shapekey enhancements seem to cause a problem on some old meshes, destroying basis shape just by tabbing in and out of edit mode
selecting the mesh and pressing 'tab tab' creates the error. Not that even though there appears to be an active shapekey, the buttons for pinning etc. are not visible.
If one first selects a shapekey and *then* tab tabs, the bug goes away. however, this can cause loss of work/destroyed meshes if the user does not notice in time.
Exact steps for others to reproduce the error
1- download the attached
2- open the file, the mesh should be selected
3- note the appearance of the shapkey panel: even though basis appears active, the pin button and associated area does not display
4- without clicking anywhere else, press tab-tab in the 3d view (enter and exit editmode)
5- note that the appearance of the mesh changes - if you save this it is not revertable
6- don't save
7- reopen the original file
8- this time, click once on the Basis Shape
9- observe that the relative checkbox, pin, and display in edit mode buttons all appear.
10- press tab tab in the 3d view
11- observe that the mesh shape does not change
In my opinion this is quite severe if/when it hits, as the user (in this case me) might not notice and end up doing a bunch of work in a file, saving and committing it. In my case, since I have SVN I can revert and redo that work. Other people may not be so lucky.