We're aware of formatting issues in some larger and/or more complex books in the online web reader in the Microsoft Edge web browser. What can be done?
Bore me to tears...
Both Edge and IE have issues with this specific book due to its complexity. Unfortunately, Microsoft has an outstanding issue with their browser engine (called EdgeHTML).
The EdgeHTML browser engine puts a hard limit on the number of CSS rules the rendering engine will attempt to process, regardless of the hardware it finds itself on. Our online books achieve their perfect layout based, in large part, on lots of CSS rules. If we hit that limit you end up with some odd formatting.
At the end of last year Microsoft announced they are discontinuing development on the EdgeHTML rendering engine and will be adopting Chromium for their Edge platform; the rendering engine inside Google Chrome.
As a consequence of this change, we're unlikely to see a fix for this problem in Edge browser until the first generation of Chromium based Edge browsers is released.
Our only option on the book side is to break the text up into several smaller books. This is awkward to manage and not a very good experience for users overall.
So given there are only a few books in the catalogue that hit this limit we're recommending Windows users try Chrome or Firefox as an alternative browser in this instance until Edge is back on track.