Hello.

This is a new installation of Wordpress 4.1 an Montezuma 1.2.4. No plugins.

On Front Page - in Firefox 35.0 - thumbnails not showing.
I can see colored images with mouse over the thumbs.

I don't see any problems in other browsers.

Here is link to website:
http://www.wood-furniture.biz/DecorTips/

Solved .

In CSS (uploads->Montezuma) generated by Montezuma:

line 595 was:

.post-thumb img.img_grayscale { 
	filter: 					grayscale(100%); 
	-ms-filter: 			grayscale(100%); 
	-o-filter: 				grayscale(100%);  
	filter: 					url("http://www.wood-furniture.biz/DecorTips/wp-content/themes/montezuma/images/gray-filter.svg#grayscale"); 
	filter: 					gray; 
	-webkit-filter: 		grayscale(1); 
	-webkit-filter: 		grayscale(100%); 
}

Removed 2 filter lines and code looks like:

.post-thumb img.img_grayscale { 
	filter: 					grayscale(100%); 
	-ms-filter: 			grayscale(100%); 
	-o-filter: 				grayscale(100%);  

	
	-webkit-filter: 		grayscale(1); 
	-webkit-filter: 		grayscale(100%); 
}

Is it correct what I did?

That works as a get around but you have lost the grey scale changing to color effect when you hover over the image.

The gray to color on hover works for me with Firefox 35.

The grayscale thumbnail issue for Firefox seems to be site-dependent. I've seen it happen on one of my sites but not others. Here is how I fixed it.

Originally Posted by CrouchingBruin

The grayscale thumbnail issue for Firefox seems to be site-dependent. I've seen it happen on one of my sites but not others. Here is how I fixed it.

I think you're right. This is site-dependent issue. Also used your tip.

Grayscale doesn't work on Android (Samsung Tab 10.2). I see colored images on start.

Grayscale doesn't work on Android (Samsung Tab 10.2). I see colored images on start.

You will not see the grayscale thumbnails on mobile devices, only the colored thumbnail. This is by design, I think because you can't hover over the thumbnails on a mobile device with a mouse.