To add a GIF to your publication:
Open the publication in Edit mode.
Click the GIF icon on the left toolbar.
The Library opens. Click Upload.
Once uploaded, select the GIF from the Library to place it on the page.
Note: You can replace the uploaded file by clicking the Change file button.
To replace a GIF already placed on the page:
Select the GIF element.
Click the GIF properties ⚙ icon, then either:
Click Change file to upload a new GIF in its place, or
Click Select from Library to use an already-uploaded GIF from your Library.