problem with images inside dialogs

### Issue type

**I'm submitting a ...** (check one with "x")

* [x] bug report
* [ ] feature request

### Issue description
Slow loading of image inside Dialog windows
**Current behavior:**
I've added image.png to folder assets/images. Its size is around 15 kB so it shouldn't be big deal but I have problem with displaying it fast inside dialog. First, the text shows and I have to wait 2-3 seconds till image shows. To display it in html I use the following code:
`

`
and path to image is inside typescript:
` imgSrc = 'assets/newImages/1520500.png';`

**Expected behavior:**
The image inside dialog should be loaded as fast as text.