How to find browser error output with Trello
Sometimes there are issues that require a bit more work to track down. One common way to do this is to look at your browser's "developer console". This is a part of your browser user interface that you can open up to see errors and warnings that are coming from the applications like Trello and Amazing Fields that are running in your browser.
The team at Balsamiq has a great guide for how to open up your developer console to track down issues.
See: Finding Your Browser's Developer Console
Once you have it open, look for error messages in the console. To send these messages to me through support you can either copy and past them or take a screenshot and send that along. Either will work find and help to track down the issues.