In the past, RM has not commented on compatibility with unreleased versions of an operating system. As they have said nothing so far, expect this will continue to be the case. Presumably they will have an update ready, or nearly ready, for any issues they may have discovered so far.
Never install a new mac OS until at least the 2nd or 3rd bug fix update. Let others find all the bugs Apple missed and wait for 3rd party developers to make needed changes. It is not like a Windows OS update but still can have problems you do not need to experience.
I haven’t heard any issues being reported with Tahoe. While we don’t support beta versions of OS we typically have users that do install it and report any issues. We will support Tahoe on the current version of RM.
Thank you for your reply. I see that this morning’s announcement of RootsMagic 11 lists macOS 26 Tahoe as a supported OS. And even more exciting, it’s got a native Mac silicon build—no more rosetta. I will be upgrading to RM 11 today!