Missing Logo in Repository

Comparing how your plugin is diplayed with your neighbour on the list here https://wordpress.org/plugins/search.php?q=custom+fields+taxonomies+light, they have 2 images on the CSS inline script, and yours only show one, the other background image url being empty.

Yours:

background-image: url(//ps.w.org/filter-custom-fields-taxonomies-light/assets/icon-256x256.png?rev=1110269
background-image: url()

Theirs:

background-image: url(//ps.w.org/advanced-custom-fields/assets/icon-128x128.png?rev=1082746
background-image: url(//ps.w.org/advanced-custom-fields/assets/icon-256x256.png?rev=1082746

If you are sure you uploaded that 128px image, in the right format and extension, it may be corrupt? Is not saved on the server properly? Maybe you will have to delete and upload it again?

The image
http://ps.w.org/filter-custom-fields-taxonomies-light/assets/icon-128x128.png?rev=1110269
is not found on the server whereas
http://ps.w.org/filter-custom-fields-taxonomies-light/assets/icon-256x256.png?rev=1110269
is, therefore the 128px picture is not on the server…

EDIT:

Here http://ps.w.org/filter-custom-fields-taxonomies-light/assets/ we can see that your 128×128 image is written not with an x but something else very similar, a × that becomes icon-128%c3%97128.png instead of icon-128×128.png!