Hi KrisMc,
Thanks for posting in the Community!
There's no reported incident with the error you're getting when trying to click the Customise look and feel under Company settings. I replicated as well in my end and is working fine.
Let's perform some basic troubleshooting steps to isolate the behavior encountered in your QuickBooks Online account. To start with, use a new incognito window or a different supported browser. Using an incognito window does not store any data file.
Here's how:
- Google Chrome: Ctrl + Shift + N
- Mozilla Firefox: Ctrl + Shift + P
- Safari: Command + Shift + N
Then, log in to QBO and access the Company settings once to customise your sales forms.
If it works fine when accessing the new incognito window,, I would recommend going back to your default browser and clear your browsers cache.
If the issue persists, kindly use a different supported browser or a different device to isolate the behavior encountered.
Post again in the Community if you have further concerns. I'll be around to help you.
