Build error: Master page file contains invalid markup

[cschwartz]

This post is part query for better ideas, and part offering to the Google search algorithm gods.

When building an HTML5 target, the build failed with this error:

Code: Select all

Build failed: Compiler: In file:///C:/some-topic.htm: Failed to parse master page file [Master page file contains invalid markup].

But that file had no change (Git confirmed), and neither did the master page, and both parsed and validated correctly. Curiouser and curiouser, if I deleted the topic, then the _next_ topic in the book would start to make builds fail. Google and the Flare forum search found 0 results.

The root cause was actually in a CSS file (spell check in a prior commit apparently changed "url" to "URL", and this caused a CSS validation failure which bubbled up to the master page that used the CSS, and then to any topic).

I can't find a way to get more accurate/verbose Flare build error messages. I found the cause by comparing with an old Git branch, and combing through changes that were outside of topic files. It took almost two days.

Does anyone have a better method for troubleshooting build errors? Or a Flare bug ID to improve the error messages?

Thanks.