CSS Conditional Rules is a CSS module that allows to define a set of rules that will only apply based on the capabilities of the processor or the document the style sheet is being applied to.
Reference
At-rules
Specifications
Specification | Status | Comment |
---|---|---|
CSS Conditional Rules Module Level 3 | Candidate Recommendation | Initial definition |
Browser compatibility
@document
rule
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome
No support No |
Edge
No support No |
Firefox Full support 61 Full support 61 Prefixed' Implemented with the vendor prefix: -moz-
Notes' Disabled by default in web pages, except for an empty Prefixed' Implemented with the vendor prefix: -moz- |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android Full support 61 Full support 61 Prefixed' Implemented with the vendor prefix: -moz-
Notes' Disabled by default in web pages, except for an empty Prefixed' Implemented with the vendor prefix: -moz- |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No | |
|
Chrome
No support No |
Edge
No support No |
Firefox
Full support 6 |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
Full support 6 |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.'
- Experimental. Expect behavior to change in the future.
- Non-standard. Expect poor cross-browser support.'
- Non-standard. Expect poor cross-browser support.
- See implementation notes.'
- See implementation notes.
- User must explicitly enable this feature.'
- User must explicitly enable this feature.
- Requires a vendor prefix or different name for use.'
- Requires a vendor prefix or different name for use.
@import
rule
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
@import
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 1 |
IE
Full support 5.5 |
Opera
Full support 3.5 |
Safari
Full support 1 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
Legend
- Full support
- Full support
@media
rule
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
@media
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 1 |
IE
Full support 6 |
Opera
Full support 9.2 |
Safari
Full support 1.3 |
WebView Android
Full support 1 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
any-hover media feature
|
Chrome
Full support 41 |
Edge
Full support 16 |
Firefox
Full support 64 |
IE
No support No |
Opera
Full support 28 |
Safari
Full support 9 |
WebView Android
Full support 41 |
Chrome Android
Full support 41 |
Firefox Android
Full support 64 |
Opera Android
Full support 28 |
Safari iOS
Full support 9 |
Samsung Internet Android
Full support 5.0 |
any-pointer media feature
|
Chrome
Full support 41 |
Edge
Full support 12 |
Firefox
Full support 64 |
IE
No support No |
Opera
Full support 28 |
Safari
Full support 9 |
WebView Android
Full support 41 |
Chrome Android
Full support 41 |
Firefox Android
Full support 64 |
Opera Android
Full support 28 |
Safari iOS
Full support 9 |
Samsung Internet Android
Full support 4.0 |
aspect-ratio media feature
|
Chrome
Full support 3 |
Edge
Full support 12 |
Firefox
Full support 3.5 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 5 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 4.2 |
Samsung Internet Android
Full support 1.0 |
calc() expressions
|
Chrome
Full support 66 |
Edge
Full support 79 |
Firefox
Full support 59 |
IE
No support No |
Opera
Full support 53 |
Safari
Full support 12 |
WebView Android
Full support 66 |
Chrome Android
Full support 66 |
Firefox Android
Full support 59 |
Opera Android
Full support 47 |
Safari iOS
Full support 12 |
Samsung Internet Android
Full support 9.0 |
color media feature
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
color-gamut media feature
|
Chrome
Full support 58 |
Edge
Full support 79 |
Firefox
No support No |
IE
No support No |
Opera
Full support 45 |
Safari
Full support 10 |
WebView Android
Full support 58 |
Chrome Android
Full support 58 |
Firefox Android
No support No |
Opera Android
Full support 43 |
Safari iOS
Full support 10 |
Samsung Internet Android
Full support 7.0 |
color-index media feature
|
Chrome
Full support 29 |
Edge
Full support 79 |
Firefox
No support No |
IE
No support No |
Opera
Full support 16 |
Safari
Full support 8 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 29 |
Firefox Android
No support No |
Opera Android
Full support 16 |
Safari iOS
Full support 8 |
Samsung Internet Android
Full support 2.0 |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
display-mode media feature
|
Chrome
Full support 45 |
Edge
Full support 79 |
Firefox Full support 47 Full support 47 Notes' Firefox 47 and later support |
IE
No support No |
Opera
Full support 32 |
Safari
Full support 13 |
WebView Android
Full support 45 |
Chrome Android
Full support 45 |
Firefox Android Full support 47 Full support 47 Notes' Firefox 47 and later support |
Opera Android
Full support 32 |
Safari iOS
Full support 13 |
Samsung Internet Android
Full support 5.0 |
Chrome Full support 79 Full support 79 Notes' See bug 970285.
Disabled' From version 79: this feature is behind the |
Edge
Full support 79 |
Firefox Full support 81 Full support 81 Disabled' From version 81: this feature is behind the |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android No support No No support No Notes' See bug 970285. |
Chrome Android No support No No support No Notes' See bug 970285. |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android No support No No support No Notes' See bug 970285. | |
grid media feature
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 10 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
height media feature
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
hover media feature
|
Chrome Full support 38 Full support 38 Notes' Before Chrome 41, the implementation was buggy and reported |
Edge
Full support 12 |
Firefox
Full support 64 |
IE
No support No |
Opera
Full support 28 |
Safari
Full support 9 |
WebView Android Full support 38 Full support 38 Notes' Before Chrome 41, the implementation was buggy and reported |
Chrome Android
Full support 50 |
Firefox Android
Full support 64 |
Opera Android
Full support 28 |
Safari iOS
Full support 9 |
Samsung Internet Android
Full support 5.0 |
inverted-colors media feature
|
Chrome
No support No |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support No |
Safari
Full support 9.1 |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
Full support 10 |
Samsung Internet Android
No support No |
Media feature expressions | Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 1 |
IE
Full support 9 |
Opera
Full support 9.2 |
Safari
Full support 1.3 |
WebView Android
Full support 1 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 3.1 |
Samsung Internet Android
Full support 1.0 |
Media query value support | Chrome
Full support 66 |
Edge
Full support 79 |
Firefox
Full support 59 |
IE
No support No |
Opera
Full support 53 |
Safari
No support No |
WebView Android
Full support 66 |
Chrome Android
Full support 66 |
Firefox Android
Full support 59 |
Opera Android
Full support 47 |
Safari iOS
No support No |
Samsung Internet Android
Full support 9.0 |
monochrome media feature
|
Chrome
Full support 1 |
Edge
Full support 79 |
Firefox
Full support 2 |
IE
No support No |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
Nested media queries | Chrome
Full support 26 |
Edge
Full support 12 |
Firefox
Full support 11 |
IE
No support No |
Opera
Full support 12.1 |
Safari
Full support 6.1 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 26 |
Firefox Android
Full support 14 |
Opera Android
Full support 12.1 |
Safari iOS
Full support 7 |
Samsung Internet Android
Full support 1.5 |
orientation media feature
|
Chrome
Full support 3 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10.6 |
Safari
Full support 5 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 11 |
Safari iOS
Full support 4.2 |
Samsung Internet Android
Full support 1.0 |
overflow-block media feature
|
Chrome
No support No |
Edge
No support No |
Firefox
Full support 66 |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
Full support 66 |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No |
overflow-inline media feature
|
Chrome
No support No |
Edge
No support No |
Firefox
Full support 66 |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
Full support 66 |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No |
pointer media feature
|
Chrome
Full support 41 |
Edge
Full support 12 |
Firefox
Full support 64 |
IE
No support No |
Opera
Full support 28 |
Safari
Full support 9 |
WebView Android
Full support 41 |
Chrome Android
Full support 50 |
Firefox Android
Full support 64 |
Opera Android
Full support 28 |
Safari iOS
Full support 9 |
Samsung Internet Android
Full support 5.0 |
prefers-color-scheme media feature
|
Chrome
Full support 76 |
Edge
Full support 79 |
Firefox
Full support 67 |
IE
No support No |
Opera
Full support 62 |
Safari
Full support 12.1 |
WebView Android
Full support 76 |
Chrome Android
Full support 76 |
Firefox Android
No support No |
Opera Android
Full support 54 |
Safari iOS
Full support 13 |
Samsung Internet Android
Full support 12.0 |
Chrome
No support No |
Edge
No support No |
Firefox Full support 80 Full support 80 Disabled' From version 80: this feature is behind the |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No | |
Chrome Full support 85 Full support 85 Notes' See bug 1051189.
Disabled' From version 85: this feature is behind the |
Edge Full support 85 Full support 85 Notes' See bug 1051189.
Disabled' From version 85: this feature is behind the |
Firefox
No support No |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android No support No No support No Notes' See bug 1051189. |
Chrome Android Full support 85 Full support 85 Notes' See bug 1051189.
Disabled' From version 85: this feature is behind the |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No | |
prefers-reduced-motion media feature
|
Chrome
Full support 74 |
Edge
Full support 79 |
Firefox
Full support 63 |
IE
No support No |
Opera
Full support 62 |
Safari
Full support 10.1 |
WebView Android
Full support 74 |
Chrome Android
Full support 74 |
Firefox Android
Full support 64 |
Opera Android
Full support 53 |
Safari iOS
Full support 10.3 |
Samsung Internet Android
Full support 11.0 |
Chrome
No support No |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No | |
resolution media feature
|
Chrome
Full support 29 |
Edge
Full support 12 |
Firefox Full support 8 |
IE
Full support 9 |
Opera Full support 16 Full support 16 No support 10 — 15 |
Safari No support No No support No Notes' See bug 78087. |
WebView Android
Full support ≤37 |
Chrome Android
Full support 29 |
Firefox Android Full support 8 |
Opera Android Full support 16 Full support 16 No support 10.1 — 14 |
Safari iOS No support No No support No Notes' See bug 78087. |
Samsung Internet Android
Full support 2.0 |
scan media feature
|
Chrome
No support No |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No |
scripting media feature
|
Chrome No support No No support No Notes' See bug 489957. |
Edge No support No No support No Notes' See bug 489957. |
Firefox No support No No support No Notes' See bug 1166581. |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android No support No No support No Notes' See bug 489957. |
Chrome Android No support No No support No Notes' See bug 489957. |
Firefox Android No support No No support No Notes' See bug 1166581. |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android No support No No support No Notes' See bug 489957. |
speech media type
|
Chrome
No support No |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
Full support 9.2 |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
Full support 10.1 |
Safari iOS
No support No |
Samsung Internet Android
No support No |
update media feature
|
Chrome
No support No |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
No support No |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No |
width media feature
|
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox
Full support 2 |
IE
Full support 9 |
Opera
Full support 10 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android
Full support 10.1 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 |
Chrome
No support No |
Edge
No support No |
Firefox
Full support 4 |
IE
No support No |
Opera
No support No |
Safari
No support No |
WebView Android
No support No |
Chrome Android
No support No |
Firefox Android
Full support 4 |
Opera Android
No support No |
Safari iOS
No support No |
Samsung Internet Android
No support No | |
Chrome
No support 2 — 36 |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support 15 — 23 |
Safari
Full support 4 |
WebView Android
No support ≤37 — ≤37 |
Chrome Android
No support 18 — 36 |
Firefox Android
No support No |
Opera Android
No support 14 — 24 |
Safari iOS
Full support 3.2 |
Samsung Internet Android
No support 1.0 — 3.0 | |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
IE
No support No |
Opera
Full support 15 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
Opera Android
Full support 14 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
IE
No support No |
Opera
Full support 15 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
Opera Android
Full support 14 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
Chrome
Full support 1 |
Edge
Full support 12 |
Firefox Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
IE
No support No |
Opera
Full support 15 |
Safari
Full support 3 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 18 |
Firefox Android Full support 63 Full support 63 Notes' Implemented as an alias for for Notes' Implemented as an alias for for Notes' Implemented as an alias for for |
Opera Android
Full support 14 |
Safari iOS
Full support 1 |
Samsung Internet Android
Full support 1.0 | |
Chrome
No support 2 — 36 |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support 15 — 23 |
Safari
Full support 4 |
WebView Android
No support ≤37 — ≤37 |
Chrome Android
No support 18 — 36 |
Firefox Android
No support No |
Opera Android
No support 14 — 24 |
Safari iOS
Full support 3.2 |
Samsung Internet Android
No support 1.0 — 3.0 | |
Chrome
No support 2 — 36 |
Edge
No support 12 — 79 |
Firefox Full support 49 Full support 49 Full support 46 Disabled' From version 46: this feature is behind the |
IE
No support No |
Opera
No support 15 — 23 |
Safari
Full support 4 |
WebView Android
No support ≤37 — ≤37 |
Chrome Android
No support 18 — 36 |
Firefox Android Full support 49 Full support 49 Full support 46 Disabled' From version 46: this feature is behind the |
Opera Android
No support 14 — 24 |
Safari iOS
Full support 3.2 |
Samsung Internet Android
No support 1.0 — 3.0 | |
Chrome
No support 2 — 36 |
Edge
No support No |
Firefox
No support No |
IE
No support No |
Opera
No support 15 — 23 |
Safari
Full support 4 |
WebView Android
No support ≤37 — ≤37 |
Chrome Android
No support 18 — 36 |
Firefox Android
No support No |
Opera Android
No support 14 — 24 |
Safari iOS
Full support 3.2 |
Samsung Internet Android
No support 1.0 — 3.0 |
Legend
- Full support
- Full support
- No support
- No support
- Experimental. Expect behavior to change in the future.'
- Experimental. Expect behavior to change in the future.
- Non-standard. Expect poor cross-browser support.'
- Non-standard. Expect poor cross-browser support.
- Deprecated. Not for use in new websites.'
- Deprecated. Not for use in new websites.
- See implementation notes.'
- See implementation notes.
- User must explicitly enable this feature.'
- User must explicitly enable this feature.
@supports
rule
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
@supports
|
Chrome
Full support 28 |
Edge
Full support 12 |
Firefox Full support 22 Full support 22 No support 17 — 22 Disabled' From version 17 until version 22 (exclusive): this feature is behind the |
IE
No support No |
Opera
Full support 12.1 |
Safari
Full support 9 |
WebView Android
Full support ≤37 |
Chrome Android
Full support 28 |
Firefox Android Full support 22 Full support 22 No support 17 — 22 Disabled' From version 17 until version 22 (exclusive): this feature is behind the |
Opera Android
Full support 12.1 |
Safari iOS
Full support 9 |
Samsung Internet Android
Full support 1.5 |
selector()
|
Chrome
Full support 83 |
Edge
Full support 83 |
Firefox Full support 69 Full support 69 Full support 64 Disabled' From version 64: this feature is behind the |
IE
No support No |
Opera
Full support 69 |
Safari No support No No support No Notes' See bug 199237 |
WebView Android
Full support 83 |
Chrome Android
Full support 83 |
Firefox Android Full support 64 Full support 64 Disabled' From version 64: this feature is behind the |
Opera Android No support No No support No Notes' See bug 979041. |
Safari iOS No support No No support No Notes' See bug 199237 |
Samsung Internet Android
Full support 13.0 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.'
- See implementation notes.
- User must explicitly enable this feature.'
- User must explicitly enable this feature.
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