Assembler error box only showing once

[MidnightLightning]

Given a simple program like:

SET A, 1
SET B, 2
SET C, [test+1] ; Syntax error; assembler can't handle "label plus literal" notation

:exit
SET PC, exit

:test
dat 0
dat 1
dat 2

Where there's an error on line three, The error message of "Assembler error: Invalid offset pointer, must have 1 literal/subroutine and 1 register" shows above the "Run"/"Stop" buttons when you first paste that code in, but clicking in the code editor hides the error, and it does not come back when clicking off the editor, even if the error changes. For example, change SET C, [test+1] to SET C, [tester]. Viewing source shows that the error box is updated to "Label tester was not defined (address 3)", but it remains hidden (display:none), and the error bar is still showing the line before.