Here's a case I ran into that had me puzzled, and might be what some of our users are seeing:

I started with a page that I didn't realize had an extra </div> at the end. Here's a simplified version. Live Preview started successfully (see yellow lightning bolt).

I updated some text in an existing tag and the browser updated while I typed:

I added a line to page so I could add a new paragraph. Brackets now detects the structural error in my page. There are no more updates to browser after this point. My actual page was much longer, so offending line was not in view, and I did not see the line number highlighted. The lightning bolt changed to red, but I did not notice it:

As I start to add my tag, an error is shown on the current line and browser does not update while I type, both of which are expected. Lightning bolt is still red:

After I finish adding new tag, the error switches back to end of file (which I cannot see). Lightning bolt is still red:

I reflexively hit Ctrl-S to save my page. Lightning bolt changes back to yellow! Line at end of file is still highlighted. I expected page to start updating in browser again, but it doesn't.

Obviously, the lightning bolt should stay red after last step, but is there more we can do?

• Detect structural problem from start?
• While lightning bolt is red, there is info in tooltip over icon, but maybe we could also show a twipsy? When and for how long?
• I don't always notice color changes -- maybe show a text message in status bar?