Local mp4 to webm converter: Miro videoconverter

screenrecorder that can save to gif mp4 etc: screentogif

cool scripts to create signs ( neon style this example ) codepen

to use webm's on your maps, you need to convert gif's to mp4 first (if there is no x and y size in the webm, trackmania does not eat / display it, gif's seem not to pass x and y size to the rendered webm video) >> so if you use screentogif, save as mp4 >> convert to webm with the miro video converter.

Upload the webm to a host that supports direct download, choose your sign in editor, and paste url in the painter tool.

to check if your url is baked in , open the gbx file with notepas++ or similar end check the first few lines for your url.

you should see somethign like that: https://pastebin.com/UKWJBSrH