Migration/Upgrade issue

Hello! With the demise of the "classic" browser extension, I'm finally biting the bullet and migrating from 1password 7 to 8. While the new UI is still a pretty janky and flaky compared to 7, it does at least appear to have improved dramatically since the last time I tried it, so kudos to the team- especially for restoring the cmd+\ keyboard shortcut.

As part of this migration, I had to move my logins etc. from my old standalone vault to my 1password account; I did this using the in-app migration tool, and it seems to have mostly worked in that all of the items seem to have been copied up and are syncing across machines. However, attachments do not seem to have made it. In 1password 8 on both my iPhone and my secondary test Mac, items that have attachments all show them with a "File Missing" label and icon. On my main Mac, 1password 7 has been showing the "Moving your data..." screen for more than an hour, and I'm guessing that it's gotten stuck somehow as my vault simply wasn't very large (less than a thousand items, only a handful of which have attachments, all of which are very small). Is there some other step I need to do? How will I tell when it's done? Thank you in advance for any light you may be able to shed on this. :-)

1Password Version: Not Provided
Extension Version: Not Provided
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