I can reproduce; I don't know what causes it. The steps to reproduce vary, however, and sometimes resolve themselves.
For your reference:
- https://github.com/Scirra/Construct-bugs/issues?q=getModifierState
- https://github.com/Scirra/Construct-bugs/issues/7464
- https://github.com/Scirra/Construct-bugs/issues/7456
- https://github.com/Scirra/Construct-bugs/issues/7455
The common error message is Uncaught TypeError: d.getModifierState is not a function
. The Construct Team closes all issues regarding this since it's not reproducible from a project but rather the editor itself.
To note, this issue started months ago, with the export not working if you don't preview first. However, now even that remedy doesn't work anymore. Then, the next remedy is to restart the editor. Now, that remedy also doesn't work anymore. It's practically random to me now when it will work.
I myself am stuck with this and have to call it a day from time to time when this happens.
My best guess is that some files aren't loaded properly in the editor while exporting, and this happens. I would like to dig into what's causing the issue to file a report, but the engine is so obfuscated that it's like an insult to anyone who does try to investigate, like our time doesn't matter.
Ashley, if you want us to investigate issues ourselves, at least help us and not make it hard.