When I tried clicking on a category button in the blocks palette, it gave me this error message:
notes = Browser: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36
foundIn = nb178a
faultData = java.lang.IllegalStateException: no such property: BlocksToolkit
projectId = 6365040674996224