Error: Content Security Policy?

Question

gulp.js

Please tell me how to fix this problem in Firefox.
Here is the gulp code if needed:

const gulp = require("gulp")
const rename = require("gulp-rename")
const sass = require("gulp-sass")
const pug = require("gulp-pug")
const autoprefixer = require("gulp-autoprefixer")
const sourcemaps = require("gulp-sourcemaps")
const browserSync = require("browser-sync").create()

function localHost(done){
    browserSync.init({
        server:{
            baseDir:"./"
        }
    })
    done()
}
function copyTask(done){
  gulp.src("./dev/sass/*")
      .pipe(sourcemaps.init())
      .pipe(sass({
        errorLogToConsole:true,
        outputStyle:"compressed"
      }))
      .on('error',console.error.bind(console))
      .pipe(autoprefixer({
          overrideBrowserslist:["last 2 versions"],
          cascade: false
      }))
      .pipe(rename({suffix:".min"}))
      .pipe(sourcemaps.write("./"))
      .pipe( gulp.dest("./dev/result/css/"))
      .pipe(browserSync.stream())
    done()
}

function copyTaskHtml(done){
    gulp.src("./dev/index.pug")
        .pipe(pug({
            errorLogToConsole:true,
            pretty:true
        }))
        .on('error',console.error.bind(console))
        .pipe(gulp.dest("./dev/result/"))
        .pipe(browserSync.stream())
    done()
}

function watchTask(){
    gulp.watch("./dev/sass/**/*",copyTask)
    gulp.watch("./dev/*",copyTaskHtml)
}
gulp.task("default" , gulp.parallel(watchTask,localHost))