AutoTools Web Screen cache?

Im not sure if im doing something wrong, but is the Web Screen using any cache for images?
Im trying to change some icons by giving the icons new diffrent url's but i cant see them change?
Im setting the url's from variables.
And i have made some new icons with same name and cant see the change until after a while (5-10 times of calling the screen)
If there is cache, is there any way to clear the cache from tasker?

 

I found out a workaround..
I added ?dummy=%TIMES to the end of the image url to make the filename uniqe.