I am getting an error when trying to run a project in HTML5, a dialog box pops up “Expression (TTraits::WithPostSerialize) failed in Runtime/CoreUObject/Public\UObject/Class.h:968”. Any ideas on what may be causing this? The project runs fine in Unreal and I have not run into this error before when launching in HTML5 projects.
Hey bobschwab,
I’ve just tested a clean project on HTML5 and it seems to be working fine, so there must be something causing the issue in your specific project. Which browser are you using to test the game?
I have tested it in Safari, Firefox and Chrome. I did find today that I believe the widget is the culprit. I disconnected that in my blueprint and all loads fine so now I need to explore that.
I’m glad that you were able to get your project to load. As a result of it currently working, I’m going to mark this topic as resolved. However, if you are able to discern the cause of the error with regards to the widget, please do leave a comment to reopen the thread so that I can attempt a repro on my end and get a ticket in if necessary to fix any issues.
Let me know if you have further questions regarding this.
Thank you
Hey @bobschwab, I’m having the exact same error. My project is made up entirely of Widgets, so disconnecting them isn’t an option for me. Did you ever figure out what specifically was causing the issue?
Cheers,
Tom
No, I never did find the culprit and we ended up moving our project off the Unreal Engine and using three.js to run things.
Today, I faced this issue in UE4.20.3
I wonder what I am supposed to do after finding out that I can’t use spawnable widgets in the HTML5…
I hope they fix this or show us a tweak to work around it.
After spending a couple of hours debugging concerning this error.
It appeared that the issue was due to the Font of the Text in the Widget. After changing it, it finally worked for me.