[css-will-change] Add some more notes and clarifications to will-change:contents.

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extra : rebase_source : db2306cdce4d55b6f8d8e57be3b699a9b0eca04b
[css-display] Fix Abstract.

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extra : rebase_source : 79bb48a0e5782c5c614a0c2b7338059c5de32190
[css-text] Rely on Bikeshed to handle cross-spec links.

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extra : rebase_source : 5e5214f27f96265dfe5ec443e0742ae3c2a9498c
[css-text] Update DoC

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extra : rebase_source : 20fd07ac93366235b9072193ef292dbecc34cce2
Revert span.note styling change
[css-flexbox] markup tweak

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extra : rebase_source : 607cedefdfbf1e2ac1cc7a95b13940e95a7295a7
[css-flexbox] Define that if a flex item has a definite flex basis, its definite (and equal to flexed size) for the purpose of resolving percentages.
[css-flexbox] Update DoC

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extra : rebase_source : c23fe3f97c78774506eab4ad902ae115cfa562a4
[css-flexbox] What was I smoking? Make the edit from 9954fb9b2adf actually be correct.
[css-flexbox] I allow max-height to transfer into a max-width constraint when there's an aspect ratio, but didn't allow height to transfer into width.
[css-flexbox] Nope, I really did mean to only look at width/height, not flex-basis, when doing min-width:auto. Also added explanatory note.
XP checkbox handling, fix hiding of open issues

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extra : rebase_source : b2a88382c70703c4e6a77b20181c281af2115ecd
[css-flexbox] Update DoC

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extra : rebase_source : 18d9a379a46f1765f6e272da517e52dd84a949a2
[css-flexbox] Fix typo from broken S&R.
[css-flexbox] Update DoC

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extra : rebase_source : 235efd5de02966151be6b7f611f2864e0af8d23a
[css-flexbox] Update DoC
[css-flexbox] Update DoC

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extra : rebase_source : a66ef05fe39bb55d709e4fb6112a972f2f7a54cc
[css-align] Add issue about initial scroll-position being affected by content alignment.
[css-align] Flexbox align-content:stretch acts like *flex-start*, not start.
[css-flexbox] Be more clear about used vs computed flex basis in various parts.