AngularJS 1.5 pattern escape problem

Bug report

Webpack version: 5.75.0
TS-Loader version: 9.4.1
Please tell us about your environment: Windows 10

Current behavior:
I am migrating AngularJS, and some inputs have ng-pattern attribute. TS-Loader removes backslashes in regex inside this attribute and because of this regex is not valid.
In my code I have ng-pattern="/^\+[\d]{7,15}$/" and output is ng-pattern="/^\+[\d]{7,15}$/"

The same problem was reported and fixed in HTML-Loader here

Expected/desired behavior:
Please add regex processing.

tsconfig.json
{ "compilerOptions": { "baseUrl": "", "declaration": false, "emitDecoratorMetadata": true, "experimentalDecorators": true, "lib": ["es6", "dom"], "mapRoot": "./", "module": "es6", "moduleResolution": "node", "outDir": "../dist/out-tsc", "sourceMap": true, "target": "es5", "typeRoots": [ "./node_modules/@types" ] } }

webpack.config.js
module.exports = { entry: "./app/main.ts", output: { filename: "src/dist/bundle.js" }, resolve: { // Add '.ts' and '.tsx' as a resolvable extension. extensions: [".webpack.js", ".web.js", ".ts", ".tsx", ".js"] }, module: { rules: [ // all files with a '.ts' or '.tsx' extension will be handled by 'ts-loader' { test: /\.tsx?$/, loader: "ts-loader" } ] }, optimization:{ minimize: false } };

Start by reproducing the issue with the provided tsconfig.json and webpack.config.js, focusing on the ng-pattern attribute in the AngularJS input. Compare the behavior with the HTML-Loader pull request linked in the report. Done means regex backslashes are preserved in the generated output and the reported pattern remains valid.