I managed to get this working this year, the solution was to enter only the first 20 characters of my password. They do support this, it's just that the login is really messed up. Whether that login portal is embedded by Fidelity or talks to Fidelity auth from Intuit is besides the point. If my team gets a software bug and it's due to some external program, we transfer the bug to the external team. If this isn't an Intuit bug, please follow up with Fidelity to resolve the problem.
I got them to acknowledge the issue but I doubt this is something they can easily change. External teams would definitely at least add pressure on them for a workaround.
