We have a manuscript for a completed novel. We recently regenerated the PDF for the paperback using 3.5.1 and the page count changed. We binary searched the old PDF and the new PDF and found the first incidence of the change. A scene with text styled with Heading 2 was missing a line of space below it in the PDF created with 3.5.1 vs. the previous PDF. We double checked the Heading 2 style in the Compile->Format and the line space is set to 2.0 but it clearly generated a 1.0 line space after the text styled with Heading 2.
[We are futzing with space after paragraph setting in the compile->format for Heading 2 and have a workaround to get close to the same spacing.]
There were indeed some style-based fixes in 3.5.1 that could in theory create a scenario that you thought was beneficial but in fact was a bug, and now that it is fixed, it has gone back to how it should be working. In 3.5 some styles (like headings) could execute their formatting on the following lines as well—thus doubling the spacing in some cases.
Am I to understand you have fixed this though, by changing your line height back to a 2.0 multiplier (as you note, this isn’t precisely spacing after, that’s a separate setting that takes a fixed height measurement rather than a multiplier, but if that’s ultimately the look you’re trying to achieve, you might look into using that instead of the line-height. Personally for headings I prefer to use 1.0 for the line-height and use the spacing before/after controls for all padding design desires).
Thank you for the quick response!