It seems like moz-columns-* does not create new columns when there is a constraint on the 'height' size property. See attached url (http://vingtetun.org/tmp/colums.html)
Note that it is different from bug 531793 that claim that it works when the 'height' is defined but not the 'max-height', so it could be a regression.
I have just tried with an old (really!) version of Firefox 3.5.16 and it works correctly. So this is a regression.
More useful, mozregression give me this: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=9f29daaecbcc&tochange=6f4f2e53694b
And in particular this changeset seems related: http://hg.mozilla.org/mozilla-central/rev/93b804e5f3f5 - this is bug 695222 - Implement column-fill property of CSS3 spec
Adding |-moz-column-fill: auto| seems to fix my problem. Not sure if it is normal or not?
Yes, we changed to follow the spec.