I’ve uploaded my logo as png file. It seems a little small. But when I try to increase the size of the logo under :
Appearance->Customize->Header->Logo->Logo Image Maximum Width, the logo size does not change whether I pick 100 pixels or 500 pixels.
Logo image size is also limited by the header height option. Try to increase it in Theme Settings -> Header -> Header layout.
We don’t see any problems with loading speed for this image on your website.
Thank for your help. I was able to get the right size for the logo.
Now for the favicon. I have uploaded the favicon and placed it using the Customize->General-> Favicon panel but the website still shows “B” favicon.
You need to clear your browser cache to see the changes after update. Here is a website with tutorials and guides how to clear the cache in different browsers and devices http://www.refreshyourcache.com/en/home/