We have discovered an odd issue, first on the WIki's. If the Wiki extended past the fold, the navigation-list div would not populate with the widget functions unless we resized the screen. It seems the issue is relative to if the navigation-list class is in view or not.
Before resize:
After resize:
This happens on my site too! I haven't ever been able to track it down. I'm still on 11, but I just checked my v12 stage and could reproduce it:
I opened a case on this issue a while back (1117386) and was told:
It seems this is happening due to a custom style applied on this site to the body tag:
overflow-x: hidden
This rule causes Chrome and Firefox (at least) to interpret overflow-y (automatically) as 'auto' even when set explicitly to 'visible'. This style should be removed to resolve the issue.
You can find this style by going to Admin>Interface>Theme Studio>Social Site>Style Sheets>sugarcrm.less
In that sugarcrm.less file, the referenced line of code is: .actions .navigation-list {overflow-x: visible;}
However, that was added by one of my (former) coworkers to help fix this exact issue, but we weren't sure we were targeting the correct containers.
I brought this up in another conversation too as I thought it was related, but it didn't seem to be: Missing Send / Reply buttons in rich text editor
So, I don't have an answer, but I'm hoping maybe this info can help someone track this down 
