The "How to Format/Tag" boxes that pop up on the right sidebar when on a question edit page use less-accessible "lists" with the "►" character. For example, there's this in "How To Tag":
► complete the sentence: my question is about...
► use tags that describe things or concepts that are essential, not incidental to your question
► favor using existing popular tags
The page's markup claims that this is just regular text, not a list, using
Thus, when a screen reader encounters this, it will just read off the name of the Unicode symbol, followed by the text, as if it was a regular paragraph. This is instead of treating it as a list, for example by announcing a "list of 6 items" and then each item's position as "3 of 6" or similar. It also breaks anything else that relies on list behavior. If a user has a keyboard shortcut to jump back to the start of the list they're currently reading, that won't function because the page's markup says there isn't a list.
Curiously, the "How to Edit" box doesn't have this problem. It's properly marked up with
<li> elements inside a
<ul>; the only annoyance to a screen reader user would be that the Unicode symbol is read off when looking at the list element.
Please use proper list formatting for the "How to Format/Tag" lists as well. If it's important to maintain the ► character for style reasons, then just follow the model of "How to Edit".