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This is a page from the
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Some other places to find information are the
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CSS Gap Decorations Level 1 Updated Working Draft
By
Kevin Babbitt
March 6, 2026
Permalink
Categories:
Uncategorized
The CSS Working Group has published an updated Working Draft of
CSS Gap Decorations Level 1
This module builds upon existing support for column rules in multicolumn layout. It extends support for gap decorations to other container layout types such as grid and flex. It also introduces several new properties to support decorations in the row direction, as well as additional controls such as styling and placement variations.
This updated draft includes one major change and two new major features since the FPWD:
The former
-outset
properties are now
-inset
, with positive/negative semantics adjusted accordingly.
Authors can now specify different decoration offsets for edges vs. interior intersections, and start vs. end sides.
Authors can now control visibility of gap decorations next to empty areas using the
*-rule-visibility-items
properties.
A number of smaller changes based on author feedback and CSSWG discussion are also included. A complete list can be found in the
Changes section
Please send feedback by either
filing an issue in GitHub
(preferable) or sending mail to the (
archived
) public mailing list
www-style@w3.org
with the spec code (
[css-gaps-1]
) and your comment topic in the subject line. (Alternatively, you can email one of the editors and ask them to forward your comment.)
Minutes Telecon 2025-10-08
By
Dael Jackson
October 9, 2025
Permalink
Categories:
resolutions
Resolved:
Accept the keywords from
this comment
Issue #12611
: Set of actions for animation triggers)
Resolved:
Make offsetParent spec match reality (
Issue #12392
: offsetParent spec says that we return elements from open shadow trees, no browser does)
The discussion around
issue #12436
(Combinator to get from `interestfor` invoker to its target) pointed toward the issue needing a general solution, not a specific one. Some of it would be idref(), however there is also a need to spec the invoked relations as well as the DOM relationship. Discussion will return to the issue.
Stopping events wasn’t quite the right solution for
issue #12437
(Add an `::interest-button` pseudo element to interest invokers) so masonf will add a new summary to the github issue and discussion will continue.
There was concern about limiting the solution for
issue #10258
(Handling popover default styles) to only be when the alignment is `dialog`. Time ran out on the call to discuss which option was preferred.
Full Meeting Minutes
CSS Anchor Positioning Level 1 Updated Working Draft
By
fantasai
October 7, 2025
Permalink
Categories:
publications
The CSS Working Group has published an updated Working Draft of
CSS Anchor Positioning Level 1
. This specification extends absolute positioning to allow a box to size and position itself relative to one or more “anchor boxes” elsewhere on the page. See
previous draft announcement
This update adds a number of refinements since the previous Working Draft, including some changes to default alignment behavior and renaming the
x/y-self-
keywords in
position-area
to
self-x/y-
. Changes since the last Working Draft are listed in the
Changes section
(We also published updates to
CSS Positioned Layout Level 3
CSS Positioned Layout Level 4
, and
CSS Overflow Level 3
to fix some minor issues and ensure proper cross-linking across these four specs.)
Please send feedback by either
filing an issue in GitHub
(preferable) or sending mail to the (
archived
) public mailing list
www-style@w3.org
with the spec code (
[css-anchor-position-1]
) and your comment topic in the subject line. (Alternatively, you can email one of the editors and ask them to forward your comment.)
Minutes Telecon 2025-09-24
By
Dael Jackson
September 25, 2025
Permalink
Categories:
resolutions
Resolved:
Update WD of
css-images-4
Issue #12756
: Updated WD of CSS Images 4)
The group was given an overview of the proposal to address
issue #12218
(How do min/max block sizes affect bottom margin collapse with last child?); first resolve intrinsic height, not including end margins of contents, then check the actual height, and if they’re the same we allow collapse. Concerns were raised about the implications of how the proposal would handle height:auto and calc-size(). Discussion will return to the issue and a few interested folks will discuss more offline.
Resolved:
When resolving align-content:normal on a table cell, we use safe alignment (
Issue #12220
: Does `vertical-align` on table cell set `align-content` safely or not?)
Resolved:
width:max-content prevents table-layout:fixed from working (
Issue #10937
: What sizing keywords allow fixed table mode?)
In order to determine the best solution for
issue #12732
(position-visibility: anchors-visible should be clear about when is visibility determined), the group will start by trying to understand what types of clipping should position-visibility be checking for. Once that is clear, the group can move on to answer some sub-questions.
Resolved:
‘any’ keyword is allowed wherever ‘span-all’ is allowed, and omitted values that would default to ‘span-all’ default to ‘any’ for queries (
Issue #12610
: Add `any` keyword support to `anchored(fallback)` container queries)
Resolved:
No change for the default, we’ll investigate a switch (
Issue #12682
: fallback-position behavior: spec vs. expectation)
Resolved:
Syntax of animation-trigger is [`dashed-ident` `behavior/actions`]+# (
Issue #12652
: animation-trigger CSS syntax)
Full Meeting Minutes
Minutes CSS Values Breakout 2025-09-24
By
Dael Jackson
September 24, 2025
Permalink
Categories:
resolutions
CSS Values 5
Breakout
Resolved:
Make type(`url`) invalid in the attr() function (for now) (
Issue #5079
: attr()’s url type seems wrong)
Resolved:
Simplify as much as possible (combining items when it can) for computed value (
Issue #12290
: Computed (vs used) value of mix() functions)
Resolved:
Work on this in the next level (in consideration of all the complications outlined above) (
Issue #11941
: Allow `if()` in descriptors)
Resolved:
type() values are parsed just as in custom properties. Other attr() type values (units % etc) are literals. Add a ‘number’ keyword for literal numbers (
Issue #12479
: Clarify how `attr-unit` should be parsed)
Resolved:
Add color-scheme() test to both @container queries and if(). Open issue on what color-scheme() returns when used in color-scheme property (
Issue #10577
: Using `if()` to do dark/light switching of image urls)
Resolved:
Explore options for making a syntactic distinction between input and interpolation options (
Issue #12348
: *-interpolate() grammar can lead to confusing values)
Full Meeting Minutes
Minutes Telecon 2025-09-17
By
Dael Jackson
September 18, 2025
Permalink
Categories:
resolutions
Resolved:
Drop the fullscreen-* vars (
Issue #11899
: Add environment variables defined in WebKit)
Resolved:
Publish FPWD
css-env-1
Resolved:
Add !important to UA stylesheet rule for the inert attribute (
Issue #12049
: The interactivity property should not be included in the all shorthand)
Resolved:
Add element.pseudoAll that returns a list of CSSPseudoElement (
Issue #12162
: Add a property to retrieve plural instances of pseudo elements with the same selector)
Resolved:
Go with ::clear-icon and ::reveal-icon (
Issue #11845
: Password visibility toggle)
Several folks gave an overview of
issue #12132
(Using logical keywords in background-position shorthand with multiple backgrounds) and, in discussing details, realized that creating a through write up would help further discussions and focus around the various considerations necessary.
Resolved:
Add a flexbox level 2 with flex balance feature, syntax TBD (
Issue #3070
: Add flex-wrap: balance;)
Full Meeting Minutes
Masonry Spec Update and Open Issues
By
fantasai
September 18, 2025
Permalink
Categories:
publications
The CSS Working Group has published an updated Working Draft of
CSS Grid Layout Level 3
, which defines masonry layout. Updates in this revision include defining “dense packing” for masonry, and clarifying baseline alignment and automatic track repetition. As
published earlier
, masonry layout re-uses the
grid-*
templating properties and the spec has sketched out an
item-flow
proposal to control orientation and placement order. See the WebKit Blog’s
Item Flow, Part 1: A new unified concept for layout
post for an overview of this idea.
There remain some major syntax questions open, which the Working Group is interested in broader feedback on:
Enabling masonry layout: what
display
name to use?
This is a bit of a bikeshedding question, but we do want it to feel like masonry (essentially 1-axis grid layout) is a variation on grid layout (2-axis grid layout), so the CSS Working Group is looking for ideas that incorporate the keyword
grid
somehow.
Interpreting row vs column in masonry layouts
This starts to get into questions of what’s obvious at first glance vs what’s obvious when you integrate it with the rest of CSS, and the answers thus far are… murky. It would be good to get more authoring perspective here.
If you anticipate using masonry layouts, we’d appreciate your perspective on what would create the most intuitive (and error-resistant) system for you to learn and use, so let us know your thoughts!
As always, you can send feedback by either
commenting on or filing an issue in GitHub
(preferable) or sending mail to the (
archived
) public mailing list
www-style@w3.org
with the spec code (
[css-grid-3]
) and your comment topic in the subject line. (Alternatively, you can email one of the editors and ask them to forward your comment.)
Minutes CSS Overflow Breakout 2025-09-17
By
Dael Jackson
September 17, 2025
Permalink
Categories:
resolutions
CSS Overflow
Breakout
Resolved:
Clarify the interaction between nowrap and block ellipsis (
Issue #12811
: nowrap and block-ellipsis)
Resolved:
Rendering should be equivalent to line breaking at that soft wrap opportunity, and applying white space processing part 2 before inserting ellipsis at the end (
Issue #12008
: Interaction between whitespace collapsing and line-clamp)
Resolved:
The region break set by line-clamp ignores widows/orphans (
Issue #9235
: How does `widows` and similar properties affecting fragmentation interact with `continue: discard`?)
Resolved:
Close no change until/unless users complain (
Issue #12663
: How do empty blocks affect line-clamping by height?)
Resolved:
Floats do not increase the height of a line clamp container. They are clipped to its content edge. (
Issue #12665
: Floats and line-clamp)
Full Meeting Minutes
Minutes Telecon 2025-09-10
By
Dael Jackson
September 12, 2025
Permalink
Categories:
resolutions
The group discussed the possible ways to address the fingerprinting issue raised in
issue #10372
(Mitigating fingerprinting for AccentColor/AccentColorText) A focus of the conversation was if tainting the color so it paints correctly but doesn’t return an exact value could address this issue. The potential path forward would be tainting by propagating a computed color plus an additional bit. Concerns were expressed that if the group couldn’t figure out how to get AccentColor/AccentColorText to paint correctly then the feature itself would not have value.
Resolved:
Change ‘direction’ to ‘scrolled’, discuss keywords later (
Issue #12623
: Disambiguate scrollable/direction when along axis/towards edge)
There wasn’t disagreement with the proposal raised in
issue #12652
(animation-trigger CSS syntax) to have the event or action be optional in the new trigger() property. However, there was still a lot of discussion on the broader syntax and bikeshedding so a resolution on this specific question felt premature.
Full Meeting Minutes
Minutes Telecon 2025-09-03
By
Dael Jackson
September 5, 2025
Permalink
Categories:
resolutions
Resolved:
Change the definition to ‘must do nothing’ and make the computed value remain (
Issue #12015
: What to do with `blink` value in `text-decoration`?)
Resolved:
Change initial value of item-tolerance to ‘normal’ (
Issue #12111
: Make `item-tolerance` initial value `normal`)
The group discussed the options in github for
issue #12176
(Giving ::scroll-marker-group a name (and optionally text))
There was disagreement about if this type of labeling is the scope of CSS or the scope of HTML. :before and :after allow the labeling so there is a precedent, however a11y guidance is away from that use case so it’s unclear if it’s a path that should be followed.
General questions about scroll markers being in CSS were also discussed with this as another example of how this property blurs the lines between CSS and HTML.
Discussion will return to github with examples added to hopefully make the issue less abstract.
Resolved:
line-clamp: integer with a height constraint clamps by height or by lines, depending on what comes earlier, pending compat issues (
Issue #12041
: Can you line-clamp by both a number of lines and a height at the same time?)
Full Meeting Minutes
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