[kcmkwin/tabbox] Update window thumbnails
Test Plan: Preview the Thumbnails task switcher: {F6293654} Reviewers: #kwin, davidedmundson Reviewed By: #kwin, davidedmundson Subscribers: kwin Tags: #kwin Differential Revision: https://phabricator.kde.org/D15831
Before Width: | Height: | Size: 52 KiB After Width: | Height: | Size: 26 KiB |
Before Width: | Height: | Size: 63 KiB After Width: | Height: | Size: 37 KiB |
Before Width: | Height: | Size: 75 KiB After Width: | Height: | Size: 56 KiB |
Before Width: | Height: | Size: 61 KiB After Width: | Height: | Size: 23 KiB |