Angular SASS (.scss) stripping out properties. How do I prevent this so I can embed duplicate properties for cross browser compatibility?
To duplicate, create a new angular 7.2 project
{
"name": "default-app",
"version": "0.0.0",
"scripts": {
"ng": "ng",
"start": "ng serve",
"build": "ng build",
"test": "ng test",
"lint": "ng lint",
"e2e": "ng e2e"
},
"private": true,
"dependencies": {
"@angular/animations": "~7.2.0",
"@angular/common": "~7.2.0",
"@angular/compiler": "~7.2.0",
"@angular/core": "~7.2.0",
"@angular/forms": "~7.2.0",
"@angular/platform-browser": "~7.2.0",
"@angular/platform-browser-dynamic": "~7.2.0",
"@angular/router": "~7.2.0",
"core-js": "^2.5.4",
"rxjs": "~6.3.3",
"tslib": "^1.9.0",
"zone.js": "~0.8.26"
},
"devDependencies": {
"@angular-devkit/build-angular": "~0.13.0",
"@angular/cli": "~7.3.9",
"@angular/compiler-cli": "~7.2.0",
"@angular/language-service": "~7.2.0",
"@types/node": "~8.9.4",
"@types/jasmine": "~2.8.8",
"@types/jasminewd2": "~2.0.3",
"codelyzer": "~4.5.0",
"jasmine-core": "~2.99.1",
"jasmine-spec-reporter": "~4.2.1",
"karma": "~4.0.0",
"karma-chrome-launcher": "~2.2.0",
"karma-coverage-istanbul-reporter": "~2.0.1",
"karma-jasmine": "~1.1.2",
"karma-jasmine-html-reporter": "^0.2.2",
"protractor": "~5.4.0",
"ts-node": "~7.0.0",
"tslint": "~5.11.0",
"typescript": "~3.2.2"
}
}
Add a "teststyle" class to any element in a component.
<div style="text-align:center" class="teststyle">Hello
</div>
<router-outlet></router-outlet>
In the component's corresponding .scss file apply
.teststyle
{
background: #a64bf4;
background: -webkit-linear-gradient(right, #6ab443, #04a95f, #00d421);
background: -o-linear-gradient(right, #6ab443, #04a95f, #00d421);
background: -moz-linear-gradient(right, #6ab443, #04a95f, #00d421);
background: linear-gradient(right, #6ab443, #04a95f, #00d421);
}
The angular pre-processor strips out everything except the first property and last property.
The corresponding css looks like this. -webkit-linear-gradient, -o-linear-gradient and -moz-linear-gradient are not int he transpiled css/js file. This is a tarnspilation issue, not a browser issue.

When I use straight css I see this, which is correct.
Also including angular.json
{
"$schema": "./node_modules/@angular/cli/lib/config/schema.json",
"version": 1,
"newProjectRoot": "projects",
"projects": {
"default-app": {
"root": "",
"sourceRoot": "src",
"projectType": "application",
"prefix": "app",
"schematics": {
"@schematics/angular:component": {
"style": "scss"
}
},
"architect": {
"build": {
"builder": "@angular-devkit/build-angular:browser",
"options": {
"outputPath": "dist/default-app",
"index": "src/index.html",
"main": "src/main.ts",
"polyfills": "src/polyfills.ts",
"tsConfig": "src/tsconfig.app.json",
"assets": [
"src/favicon.ico",
"src/assets"
],
"styles": [
"src/styles.scss"
],
"scripts": [],
"es5BrowserSupport": true
},
"configurations": {
"production": {
"fileReplacements": [
{
"replace": "src/environments/environment.ts",
"with": "src/environments/environment.prod.ts"
}
],
"optimization": true,
"outputHashing": "all",
"sourceMap": false,
"extractCss": true,
"namedChunks": false,
"aot": true,
"extractLicenses": true,
"vendorChunk": false,
"buildOptimizer": true,
"budgets": [
{
"type": "initial",
"maximumWarning": "2mb",
"maximumError": "5mb"
}
]
}
}
},
"serve": {
"builder": "@angular-devkit/build-angular:dev-server",
"options": {
"browserTarget": "default-app:build"
},
"configurations": {
"production": {
"browserTarget": "default-app:build:production"
}
}
},
"extract-i18n": {
"builder": "@angular-devkit/build-angular:extract-i18n",
"options": {
"browserTarget": "default-app:build"
}
},
"test": {
"builder": "@angular-devkit/build-angular:karma",
"options": {
"main": "src/test.ts",
"polyfills": "src/polyfills.ts",
"tsConfig": "src/tsconfig.spec.json",
"karmaConfig": "src/karma.conf.js",
"styles": [
"src/styles.scss"
],
"scripts": [],
"assets": [
"src/favicon.ico",
"src/assets"
]
}
},
"lint": {
"builder": "@angular-devkit/build-angular:tslint",
"options": {
"tsConfig": [
"src/tsconfig.app.json",
"src/tsconfig.spec.json"
],
"exclude": [
"**/node_modules/**"
]
}
}
}
},
"default-app-e2e": {
"root": "e2e/",
"projectType": "application",
"prefix": "",
"architect": {
"e2e": {
"builder": "@angular-devkit/build-angular:protractor",
"options": {
"protractorConfig": "e2e/protractor.conf.js",
"devServerTarget": "default-app:serve"
},
"configurations": {
"production": {
"devServerTarget": "default-app:serve:production"
}
}
},
"lint": {
"builder": "@angular-devkit/build-angular:tslint",
"options": {
"tsConfig": "e2e/tsconfig.e2e.json",
"exclude": [
"**/node_modules/**"
]
}
}
}
}
},
"defaultProject": "default-app"
}

Angular uses Autoprefixer to add any needed vendor prefixes and remove unneeded ones. Basically you don't need to worry about adding any since they will be added for you. The ones that are being removed are because they are not needed.
Check out: https://caniuse.com/?search=linear-gradient for usage and support
-webkit-linear-gradientis only needed for-o-linear-gradientis only needed for Opera 11.5 and Opera mobile 12 (released 2011-2012) which is 0% of worldwide browsers-moz-linear-gradientis only needed for Firefox 3.5-15 (released 2010-2012) which is 0.01% of browsersIf you still want/need to support CSS gradients for 10+ year old browsers with 0% usage in a version of Angular that came out in 2018 you can just add a
src/browserslistfile (related question here) which you can read about that file format here