[css-align] Should last-baseline's fallback alignment be safe or unsafe?

[tabatkins]

The "fallback alignment" for last-baseline alignment is specified as "end". However, should this be "safe" or "unsafe"?

There are two ways we use the fallback alignment:

• If the item requests baseline alignment, but it's not in a context that allows it, we use the fallback alignment instead. In this case, "safe end" is probably best, as it doesn't hide any content.
• After we align all the baselines, we then use the fallback alignment to align the group as a whole within the shared alignment context. In this case, "safe end" is again probably best.

[css-meeting-bot]

The CSS Working Group just discussed Should last-baseline's fallback alignment be safe or unsafe?.

The full IRC log of that discussion

Topic: Should last-baseline's fallback alignment be safe or unsafe?
github: https://github.com//issues/1611
TabAtkins: fallback alignment is used in 2 cases. If you trya nd use baseline- alignment but the element isn't in a context to do any baseline aligning it doesn't have a size it can baseline align. It ususe fallabck. Other is afte ryou've done the baseline alignment you then align the group according to your fallback alignment.
TabAtkins: Problem is with an end alignment do we use safe end or unsafe end. There's arguments on both. It's better to shift down when it's too small then to lose part of the content. I don't believe there's a strong author intent to go into the unscrollable. I think it both cases it's better to do the safe end alignment.
astearns: diff between safe and unsafe?
TabAtkins: If container is smaller then element end alignment aligns to two edges and you could get unscrollable. That's unsafe. Safe is if it happens we swithc to start alignment so it scrolsl down.
astearns: Got it. Seems reasonable
Rossen_: Last time we decided we fallback to end if we do last baseline. In an overconstraint now it's start?
TabAtkins: This is unrelated. IT doesn't trigger in the same cases as discussed last week.
Rossen_: Why not?
TabAtkins: Last week we were dealing with a stretching element forced by a max width to be too small. This is things large than the container. It's a different set of elements.
fantasai: Also it effects everything...you could interp 2 ways. 1 is we break alignment so if it overflows and the other doesn't we don't overflow. Or they continue to align and they both overflow and then do they align to bottom or top.
fantasai: OTher was just about one item and how it relates.
start and end rather than bottom and top
Rossen_: And this is because we fallback on end and we dont' have the problem with first because we fallback to start.
Rossen_: Got it.
I support Tab's proposal here.
Rossen_: Do we have any other cases where combination of end and unsafe is the default?
TabAtkins: I don't think anything else falls back to end.
Rossen_: Even in explicit end the default is safe?
tantek: Determined by layout mode.
s/tantek/ TabAtkins
Rossen_: Now if we have something fallback to end would safe and unsafe be based on layout?
fantasai: I think we changed it so everything is unsafe by default. This is a fallabck to it's different.
Rossen_: Now I'm starting to be less okay because we'll have cases were I forgot one property and half my items shift in weird ways and I don't know why.
TabAtkins: We're not proposing a control, so it's not leaving off anything. You shouldn't make that decision because it's a secondary alignment where the one you spec doesn't fully apply.
Rossen_: What I'm saying is I'll have two items, one last baseline one end. IN which case the one with last baseline it fallsback to end. IF we're not overconstraint they look same. As soon as you overconstraing one because scrollable and one not scrollable direct and that's weird and people will be confused.
Rossen_: That's why I wanted to walk abck from the behavior of the explicit end or start and what kind of safe/unsafe handling we have there.
fantasai: That's a fair point.
dbaron: You can specify safe start and safe end. IT's saying fallback for last baseline is safe end.
TabAtkins: Yeah.
Rossen_: What I'm tryign to say is if we made the explicit decision that everything fallback mostly to unsafe, why make an exception? If that's not the case maybe we revisit the fallabck to unsafe, but I don't see why to do that.
TabAtkins and fantasai : can't change unsafe fallack
Rossen_: We have the fallback to go back to end, can we try and do unsafe there ands ee if we have to change later with impl feedback?
TabAtkins: Without any way to change safe/unsafe (and we're not proposing a control) there's no way to get the otehr and the one value we can expose should be the one that guar. to not hide content.
astearns: I'm confused why it's better for this case but not the default.
TabAtkins: We already had centering and alignment based on margins in flexbox and that was safe. We made them do the other behavoir to let you get them. When we moved to alignment we felt it would be useful to allow a control.
astearns: It's just historical and backwards compat constraint.
TabAtkins: Maybe. Id on't think it was unreasonable for flexbox to default to unsafe because there was a control for safe. baseline-alignment can't mimic itself with margins. We either have to expose a toggle or make a choice and I'l like to avoid syntax complexity of a toggle for this edge case.
astearns: I can see both sides. I like that it will default safe so in this edge case you won't lose content, but since it's a tiny edge case I can see keeping it same as the other default alignment.
Rossen_: I'm going to be okay with either. I wanted to point out consistancy is always good. BUt I see losing content as bad as well which will happen with explicit end already.
astearns: We're out of time. I suggest we let log bot put this in the issue, let it sit for a week, and decide next week. If there are additional thoughts please add to the issues

[css-meeting-bot]

The CSS Working Group just discussed Should last-baseline's fallback alignment be safe or unsafe?.

The full IRC log of that discussion

Topic: Should last-baseline's fallback alignment be safe or unsafe?
github: https://github.com//issues/1611
Rossen_: We discussed last week, but didn't resolve as far as I remember.
Rossen_: We wanted to gather any additional thoughts on GH. There were no updates. Do we feel like we have enough to resolve or do wew leave to F2F?
Rossen_: Last week we couldn't get to a solution going back and forth a few times.
Rossen_: We didn't resolve due to time constraints. But we also had this back and forth about if this makes the most sense and the most consistant with other alignments and their default behavior in overconstraint scenarios.
fantasai: Seems we didn't have consensus b/c good arguments in both directions.
fantasai: Prob what we need is actual use case scenarios to come up with a r eason for one being better.
Rossen_: As I mentioned, I can be persuaded either way. I favor consistancy and in thsi case there was some inconsistancywith the way fallback occurs for safe and unsafe b/c descrpency between basline-laign and align end.
fantasai: There's 2 kinds of align. safe and unsafe. We could be consistant with either one.
Rossen_: Right.
fantasai: I'm okay defering to F2F.
fantasai: I'm hoping at F2F people will h ave something concrete for one or the other.
Rossen_: I don't mind

[css-meeting-bot]

The CSS Working Group just discussed Should last-baseline's fallback alignment be safe or unsafe?.

The full IRC log of that discussion

Topic: Should last-baseline's fallback alignment be safe or unsafe?
github: https://github.com//issues/1611
fantasai: WE discussed at F2F, wanted more feedback. I don't think we got any.
fantasai: We need feedback from authors to know if there's a reason to do one or the other. Impl wise either way is doable.
Chris: How do we plan to solicit that? Twitter poll?
fantasai: I feel this is a niche case that's hard to desc in twitter.
fantasai: If you were to have a bunch of last baseline aligned items that are taller than the row they're in, would you want them to break the last baseline alignment or overflow to the top?
fantasai: WE understand, but that's hard to convey.
Chris: It needs a blog with illustrations. Does anyone want to write such a thing?
blog post + illustrations > twitter poll
Chris: As a group we're bad at getting high quality user feedback.
fantasai: We've tried and largely it's no respponse. I can write a blog post on our blog. We don't have a commenting system that's functional. I can use css3.info as commenting.
hey I can help with the functioning comment system, if someone wants help with their blog
Chris: Sure. It can also be linked to and tweeted.
we have standards for that in #social now :D
Chris: Anything else to say?
ACTION fantasai make a blog post to get feedback on https://github.com//issues/1611
Created ACTION-860 - Make a blog post to get feedback on https://github.com//issues/1611 [on Elika Etemad - due 2017-08-23].
Chris: Anything else on this topic?

[css-meeting-bot]

The CSS Working Group just discussed Should last-baseline's fallback alignment be safe or unsafe?.

The full IRC log of that discussion

Topic: Should last-baseline's fallback alignment be safe or unsafe?
dbaron, yup, that's why dholbert filed the issue :)
Github topic: https://github.com//issues/1611
fantasai: I didn't post a blog post. I did ask jensimmons and her opinion was unsafe. That's as far as I got.
Bert: You want to continue that action.
fantasai: Yeah.
Bert: Keep that open?
fantasai: Yep.

[css-meeting-bot]

The Working Group just discussed Should last-baseline's fallback alignment be safe or unsafe?, and agreed to the following resolutions:

• RESOLVED: In this case with content that will not fit in it's container and we fail to be able to last baseline align things things will overflow in a safe direction.

The full IRC log of that discussion

Topic: Should last-baseline's fallback alignment be safe or unsafe?
github: https://github.com//issues/1611
fantasai: You have a flexbox and inside you have items with last-baseline alignment but the flexbox is less then you need we have to decide how to align them. Just like for first baseline you align and then start align at the top.
fantasai: but what if it's too small to contain all the items. In that case, what happens? Do we continue to align at the bottom and overflow the top or do we take the things that are too big and put them at the bottom and they no longer participate in base alignment.
astearns: From I can access and read safe is better, but from design unsafe is better.
myles: impl difference.
fantasai: We were generally unsure before.
myles: have we asked authors?
florian: Can we default to safe? Default ing to safe sounds...safer? And let authors opt-in.
TabAtkins: We don't let you set it. It seemed like more switches then you needed access to.
fantasai: We could make it possible to combine the keywords.
florian: I'd prefer default safe and have the keyword.
astearns: We last left this that someone would write a blog post.
fantasai: That was not done.
astearns: I don't think we should assume we will add a switch. we should decide based on probablility that this is a weird edge case so it's not worth our time to have a switch.
TabAtkins: That's why we haven't done it.
Rossen: Can we resolve on choosing safe? If someone squeaks really hard we'll solve it.
astearns: Objections to using the safe behavior in this case of last-basline alignment?
fantasai: All using the alignment properties.
astearns: In this case with content that will not fit in it's container and we faill to be able to last baseline align things things will overflow in a safe direction.
RESOLVED: In this case with content that will not fit in it's container and we fail to be able to last baseline align things things will overflow in a safe direction.