ERROR: Execution of script 'Stylish Lite' failed! Failed to execute 'insertBefore' on 'Node'

Console log:

userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:4 ERROR: Execution of script 'Stylish Lite' failed! Failed to execute 'insertBefore' on 'Node': Only one element on document allowed. (anonymous) @ userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:4 23:52:03.468 userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:4 Error: Failed to execute 'insertBefore' on 'Node': Only one element on document allowed. at eval (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:7) at Array.forEach () at HTMLHtmlElement.eval (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:7) at eval (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:7) at X.every () at X.each (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:7) at X.r.fn.(anonymous function) as after at addStyle (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:245) at apply (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:235) at eval (userscript.html?id=d44da5ec-cf15-4657-976d-54722c8d97cb:261)

Tampermonkey BETA + Opera Stable