Invisible code is copied when you paste text directly from Word (or other word processors) into Plek. This code ensures that eventual formatting is not deleted. This can be useful, but sometimes leads to conflicts. Think for example of a message that is (partly) not readable in the web browser or the Plek app. Problems like these can easily be prevented by pasting text without formatting.
In Windows, paste without formatting works in Chrome and Firefox using this shortcut: Control + Shift + V
On Mac OS, use the following combination: ⌘ + ⇧ + ⌥ + V