A fix is planned for release on Weds, January 22, 2020 6.30a PT to address the cross domains cookie behavior to be released in Google Chrome v80, scheduled for February 4, 2020.
UPDATE: the planned hotfix was released to product on the scheduled date. We have performed a series of tests and have confirmed that DocGen Packages will generate as intended. Please reach out to our support teams if you notice any peculiar behavior in your own testing, or issues following the release of Chrome 80 on Feb. 4th.
The fix will be deployed to our DocGen Engine, will not require any action on your side, and will address issues that would arise during the docgen process.
In our testing we noticed a minor annoynance in Salesforce Lightning with using Chrome 80: when clicking a link or tab to load a page that has a Visualforce page iframed in it, such as our DocGen Admin tab, a NEW tab will always be opened with the iframed content. This type of experience impacts of all Salesforce, not just our app, as we noticed the same behavior when navgiating to various places in Setup within Lightning that have a Visualforce pages iFramed in.
We will be reviewing possible solutions to the new tab experience mentioned above, as well as monitoring any changes or updates the Salesforce may release to address the issue.
Salesforce Knowledge Article
Chromium Blog on the upcoming changes