I just consider that the UX site has UX failures:
- The UI wireframe icon is similar to the image icon. Sometimes I want to post an image and I click the wireframe icon
- The wireframe dialog has an icon with an "X" at its top right corner. Anybody used to Windows OS, and that is more than 90% of people who uses computers, will think it is a close button instead of an "Hide Markup" toggle. I suggest changing it to to be a press button, its contents to be "<>" and putting it on another location.
Even if you do this, there is another problem, the full screen icon, due to its shape and location, is also very similar to a close button! - The UX website has not a link to the respective meta site; and it is an observation valid for every StackExchange subsite.