Experimental

For a given set of browsers what APIs are still considred experimental, and how long have they been experimental?

Example Comparisons
Browsers
Features

Summary

Experimental APIs

Below is a list of features that are marked as "Experimental" in Firefox and Safari

Raw Data

Quick Links:

CSS Data

API First Browser Date Last Browser Date Days in experimentation Notes
css.at-rules.media.prefers-reduced-transparency 📋Firefox5/9/2023 1181
css.properties.-webkit-column-axis Safari7/25/2012 5121
css.properties.-webkit-column-progression Safari10/22/2013 4667
css.properties.-webkit-cursor-visibility Safari10/22/2013 4667
css.properties.-webkit-hyphenate-limit-after Safari7/20/2011 5492
css.properties.-webkit-hyphenate-limit-before Safari7/20/2011 5492
css.properties.-webkit-hyphenate-limit-lines Safari7/25/2012 5121
css.properties.-webkit-line-align Safari7/25/2012 5121
css.properties.-webkit-line-box-contain Safari7/20/2011 5492
css.properties.-webkit-line-grid Safari7/25/2012 5121
css.properties.-webkit-line-snap Safari7/25/2012 5121
css.properties.-webkit-mask-source-type Safari10/22/2013 4667
css.properties.-webkit-nbsp-mode Safari6/8/2009 6264
css.properties.-webkit-text-zoom Safari9/20/2016 3603
css.properties.animation-timeline 📋Firefox2/14/2023 1265
css.properties.animation-timeline.scroll 📋Firefox2/14/2023 1265
Firefox: Zero scroll range is treated as 100% but should be 0% (see bug 1780865).Firefox: Supports the deprecated horizontal and vertical axis values, and not the x and y values.
css.properties.animation-timeline.view 📋Firefox6/6/2023 1153
css.properties.background-image.element 📋Firefox3/22/2011 5612
css.properties.block-size.fit-content_function Firefox8/10/2021 1818
css.properties.break-after.always Firefox1/7/2020 2399
css.properties.break-before.always Firefox1/7/2020 2399
css.properties.content.none_applies_to_elements Firefox8/10/2021 1818
css.properties.counter-reset.reset_does_not_affect_siblings Firefox10/20/2020 2112
css.properties.counter-reset.reversed 📋Firefox1/11/2022 1664
css.properties.font-synthesis-position 📋Firefox9/26/2023 1041
css.properties.font-synthesis-position.auto 📋Firefox9/26/2023 1041
css.properties.font-synthesis-position.none 📋Firefox9/26/2023 1041
css.properties.grid-template-columns.masonry 📋Firefox6/2/2020 2252
css.properties.grid-template-rows.masonry 📋Firefox6/2/2020 2252
css.properties.height.fit-content_function 📋Firefox8/10/2021 1818
css.properties.image-rendering.smooth 📋Firefox10/5/2021 1762
css.properties.inline-size.fit-content_function Firefox8/10/2021 1818
css.properties.margin-trim 📋Safari3/27/2023 1224
css.properties.margin-trim.block 📋Safari3/27/2023 1224
css.properties.margin-trim.block-end 📋Safari3/27/2023 1224
css.properties.margin-trim.block-start 📋Safari3/27/2023 1224
css.properties.margin-trim.inline 📋Safari3/27/2023 1224
css.properties.margin-trim.inline-end 📋Safari3/27/2023 1224
css.properties.margin-trim.inline-start 📋Safari3/27/2023 1224
css.properties.margin-trim.none 📋Safari3/27/2023 1224
css.properties.max-block-size.fit-content_function Firefox8/10/2021 1818
css.properties.max-height.fit-content_function 📋Firefox8/10/2021 1818
css.properties.max-inline-size.fit-content_function Firefox8/10/2021 1818
css.properties.max-width.fit-content_function 📋Firefox8/10/2021 1818
css.properties.min-block-size.fit-content_function Firefox8/10/2021 1818
css.properties.min-height.fit-content_function 📋Firefox8/10/2021 1818
css.properties.min-height.stretch Safari9/30/2015 3959
css.properties.min-inline-size.fit-content_function Firefox8/10/2021 1818
css.properties.min-width.fit-content_function 📋Firefox8/10/2021 1818
css.properties.mix-blend-mode.plus-darker 📋Safari3/24/2020 2322
css.properties.offset-path.margin-box 📋Safari9/16/2024 685
css.properties.overflow-block.overlay Firefox4/11/2023 1209
css.properties.overflow-inline.overlay Firefox4/11/2023 1209
css.properties.ruby-position.alternate Firefox4/19/2021 1931
css.properties.scroll-timeline 📋Firefox3/14/2023 1237
Firefox: The syntax of the shorthand property uses the fixed order of name and then the axis.Firefox: Supports the deprecated horizontal and vertical axis values, and not the x and y values.Firefox: The @scroll-timeline at-rule is replaced with the longhand properties scroll-timeline-name and scroll-timeline-axis and the shorthand property scroll-timeline.
css.properties.scroll-timeline-axis 📋Firefox3/14/2023 1237
Firefox: The syntax of the shorthand property uses the fixed order of name and then the axis.Firefox: Supports the deprecated horizontal and vertical values, and not the x and y values.Firefox: The @scroll-timeline at-rule is replaced with the longhand properties scroll-timeline-name and scroll-timeline-axis and the shorthand property scroll-timeline.
css.properties.scroll-timeline-name 📋Firefox3/14/2023 1237
Firefox: The syntax of the shorthand property uses the fixed order of name and then the axis.Firefox: The @scroll-timeline at-rule is replaced with the longhand properties scroll-timeline-name and scroll-timeline-axis and the shorthand property scroll-timeline.
css.properties.speak-as 📋Safari4/12/2018 3034
css.properties.speak-as.digits 📋Safari4/12/2018 3034
css.properties.speak-as.literal-punctuation 📋Safari4/12/2018 3034
css.properties.speak-as.no-punctuation 📋Safari4/12/2018 3034
css.properties.speak-as.normal 📋Safari4/12/2018 3034
css.properties.speak-as.spell-out 📋Safari4/12/2018 3034
css.properties.stroke-color 📋Safari3/24/2020 2322
css.properties.text-decoration-skip 📋Safari3/25/2019 2687
Chrome: Only supports the deprecated ink value.Chrome Android: Only supports the deprecated ink value.Opera: Only supports the deprecated ink value.Opera Android: Only supports the deprecated ink value.Safari: Supports only none, auto, and objects values.Safari: Supports only none, auto, and objects values.Safari on iOS: Supports only none, auto, and objects values.Safari on iOS: Supports only none, auto, and objects values.Samsung Internet: Only supports the deprecated ink value.WebView Android: Only supports the deprecated ink value.WebView on iOS: Supports only none, auto, and objects values.WebView on iOS: Supports only none, auto, and objects values.
css.properties.text-decoration-skip.auto 📋Safari3/24/2020 2322
css.properties.text-decoration-skip.none 📋Safari3/24/2020 2322
css.properties.text-emphasis-position.auto Firefox10/29/2024 642
css.properties.text-justify.auto 📋Firefox8/8/2017 3281
css.properties.text-justify.inter-character 📋Firefox8/8/2017 3281
css.properties.text-justify.inter-word 📋Firefox8/8/2017 3281
css.properties.text-justify.none 📋Firefox8/8/2017 3281
css.properties.view-timeline 📋Firefox6/6/2023 1153
Firefox: Now supports the x and y values, and also the deprecated horizontal and vertical values.
css.properties.view-timeline-axis 📋Firefox6/6/2023 1153
Firefox: Now supports the x and y values, and also the deprecated horizontal and vertical values.
css.properties.view-timeline-name 📋Firefox3/14/2023 1237
css.properties.white-space-collapse.preserve-spaces 📋Firefox3/19/2024 866
css.properties.width.fit-content_function 📋Firefox8/10/2021 1818
css.selectors.-moz-first-node Firefox1/7/2020 2399
css.selectors.-moz-focus-inner Firefox1/7/2020 2399
css.selectors.-moz-last-node Firefox1/7/2020 2399
css.selectors.-moz-list-bullet Firefox1/7/2020 2399
css.selectors.-moz-list-number Firefox1/7/2020 2399
css.selectors.-moz-progress-bar Firefox1/7/2020 2399
css.types.color.system-color.mark_marktext_buttonborder 📋Firefox1/17/2023 1293
css.types.image.element 📋Firefox11/14/2017 3183
Firefox: -moz-element() is limited to background-image, background, border-image and border-image-source.Firefox: -moz-element() is limited to background-image and background.Firefox for Android: -moz-element() is limited to background-image, background, border-image and border-image-source.Firefox for Android: -moz-element() is limited to background-image and background.
css.types.ratio.number_value Firefox6/30/2020 2224