Hi,
I would not use this 3d text anymore, it's deprecated, instead, use the new UI component.
I know for IOS you can use the link.xml, but on webgl, I don't know.
Check this thread, I created a linker wizard that gather reflection usage as you play the game and it generated the link.xml. Try this, it could work for webgl too, else I would refactor your game so that it doesn't use 3d text but the new UI system. You'll get the same effect, but it will be properly supported ( and you have all the custom actions you need on the wiki)
Bye,
Jean