(Was gonna post this as a question but I think i’ve figured it out, so posting my findings instead)
I was trying to make auto hyphens happen in preview mode using some simple css:
.el-p {
text-align: justify;
hyphens: auto;
}
It works fine on android but not at all on windows. The reason is Obsidian uses Electron on desktop which has a missing hyphenation bug. From that thread this seems to be resolved, but it’s not yet propagated into Obsidian.
I also found this plugin which might work to force hyphenation on mac but not on windows.
I thought previously this was an issue due to a missing lang attribute in Obsidian’s HTML, or due to missing hyphenation dictionaries in windows(?), but it looks like it’s all down to Electron. Manual hyphens do work by using the ­ character.
Hopefully this helps someone else looking up this same topic