Hi waskasoowaterpro,
Welcome to Community! QuickBooks Online is a versatile program with the features you need to complete your daily tasks with peace of mind. I'll be happy to provide some insight here to help you with your QuickBooks goal!
When creating an estimate for your customer, the description field is line item based and does have limitations, causing issues when converting to PDF. The message section is set by default on the custom template. With regards to the error you're seeing, it may be related to browser issues. I recommend clearing cache on your browser and then log into your QuickBooks account using a private or incognito browser to see if you get the same result.
If the issue persists, I suggest contacting us. We'd be happy to work with you directly to better determine the best course of action to resolving the outcome you're experiencing.
Please feel free to reach back out with any other questions. We'd be glad to assist!