Board Thread:Support Requests - Getting Technical/@comment-26510601-20150824001413/@comment-4731443-20150825001311

I'm not certain of the result but applying in-line CSS to the span containing each image might be enough (since as far as I know we can't style images directly because of the wikitext). Try adding the opacity property like so and make it modifiable by a template parameter as we did with file names:  Possible values are 0.0 (fully transparent) to 1.0 (opaque).