Marketplace ads, which appear along the right-hand column of Facebook’s homepage, are getting a makeover. The social network is testing a new format that stretches the image across the width of the ad and marketing copy that appears below it.

Facebook often tweaks and tests new variations of ads, but recently more attention has been given to Promoted Posts and other types of ads that appear within News Feed or on mobile devices. Currently the new design appears to be limited to permanent link pages for posts, not on News Feed, Timeline, or other pages.

The new layout is similar to Facebook’s mobile ad and mobile app install ad formats — both of which include a banner above text. A statement released by a spokesperson for Facebook read, “We have seen people respond favorably to larger images — both from people and Pages — in News Feed, and as such, we are testing this out on the right-hand side.”

Because the new ad format requires an image with different proportions than standard marketplace ads, the test also requires direct participation from advertisers. Currently, only ads from Modcloth have appeared in this format. Facebook hasn’t shared how many advertisers are a part of this test.

We don’t imagine that this ad will result much backlash from Facebook’s user base. In fact, if rolled out, the new design could improve the performance of Marketplace ads — which currently have lower clickthrough rates than News Feed ads. The one drawback is that advertisers will have to prep a different size image for multiple ads.

[Via: Inside Facebook, Image credit: Steven Depolo]