:-moz-submit-invalid
Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The :-moz-submit-invalid CSS pseudo-class is a Mozilla extension that represents any submit <button> on forms whose contents aren't valid based on their validation constraints.
By default, no style is applied. You can use this pseudo-class to customize the appearance of the submit button when there are invalid form fields.
Syntax
No syntax available: No value found in the database.
Specifications
Not part of any standard.
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
:-moz-submit-invalid | 
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 88 
From Firefox 88 the feature has been placed behind a flag. See bug 1694129. 
4-88 
 | 
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 4-88 
From version 88, the feature has been withdrawn. See bug 1694129. 
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See also
    © 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
    https://developer.mozilla.org/en-US/docs/Web/CSS/:-moz-submit-invalid