[angular] <img>: Unsafe value used in a resource URL context

Angular treats all values as untrusted by default. When a value is inserted into the DOM from a template, via property, attribute, style, class binding, or interpolation, Angular sanitizes and escapes untrusted values.

So if you are manipulating DOM directly and inserting content it, you need to sanitize it otherwise Angular will through errors.

I have created the pipe SanitizeUrlPipe for this

import { PipeTransform, Pipe } from "@angular/core";
import { DomSanitizer, SafeHtml } from "@angular/platform-browser";

@Pipe({
    name: "sanitizeUrl"
})
export class SanitizeUrlPipe implements PipeTransform {

    constructor(private _sanitizer: DomSanitizer) { }

    transform(v: string): SafeHtml {
        return this._sanitizer.bypassSecurityTrustResourceUrl(v);
    }
}

and this is how you can use

<iframe [src]="url | sanitizeUrl" width="100%" height="500px"></iframe>

If you want to add HTML, then SanitizeHtmlPipe can help

import { PipeTransform, Pipe } from "@angular/core";
import { DomSanitizer, SafeHtml } from "@angular/platform-browser";

@Pipe({
    name: "sanitizeHtml"
})
export class SanitizeHtmlPipe implements PipeTransform {

    constructor(private _sanitizer: DomSanitizer) { }

    transform(v: string): SafeHtml {
        return this._sanitizer.bypassSecurityTrustHtml(v);
    }
}

Read more about angular security here.