Using Spine version: 3.8.95, Windows 10
So I want all bones able to be selected except for one specific Unity-use IK driven bone to not be selectable (The big yellow one)
The video starts showing immediately after the bug deselected all the way up the chain (presumably the root bone that was selected) I then select the "Legs_root" bone to show its selects all still work (because they're not in the chain that houses the big yellow bone).
I select the body root, select Descendant Bones, turn on all selections. Hit space to show select is on for all bones. click the yellow bone, choose to deselect only that one. Hit space again.
Scenario 1: Immediately re-select the body bone, Select Descendant Bones >>> BUG HITS >>> all bones in the chain are now not selectable.
I tried it again - Scenario 2: Immediately re-select the upper arm bone, Select Descendant Bones, >>> BUG <<<
and again - Scenario 3: Immediately re-select the upper arm bone, Select Child Bone
selects the lower arm (not yet reached the yellow IK bone)
press space, all bones still selectable. Try again, except press select Child Bone one more time to include the Yellow bone >>> BUG >>> all bones that were selected (in this case the upper arm, lower arm, and yellow bone) now have select turned off.