Internal error: database cannot be accessed

### What is this about?

Your vault can be recovered from an automated backup. Automatic recovery will delete your current settings and preferences, and restore only your vault.

You can try to copy and restore your state file manually before you decide to restore your vault by following [these instructions](https://support.metamask.io/configure/wallet/how-to-recover-your-secret-recovery-phrase/#step-two-locate-your-vault).

Restore accounts
This behavior is unexpected and should be reported as a bug, even if your accounts are restored. [Send us a bug report.](https://support.metamask.io/)

### Scenario

**I have a lot of wallets in different portable browsers, including Chrome. When I try to transfer files from one browser to another, I get this error. I've already lost about $20 because I didn't save the seed phrase and hoped to copy the files. How can I fix my wallet files? A search in LDB for UTF-8 keyring didn't yield any results. WHAT SHOULD I DO?**

### Design

_No response_

### Technical Details

_No response_

### Threat Modeling Framework

_No response_

### Acceptance Criteria

_No response_

### Stakeholder review needed before the work gets merged

- [x] Engineering (needed in most cases)
- [ ] Design
- [ ] Product
- [ ] QA (automation tests are required to pass before merging PRs but not all changes are covered by automation tests - please review if QA is needed beyond automation tests)
- [x] Security
- [ ] Legal
- [ ] Marketing
- [ ] Management (please specify)
- [ ] Other (please specify)

### References

_No response_

No source files, tests, technical details, or acceptance criteria are named. Start by reproducing the database-access error when transferring wallet files between portable browsers and review the linked vault-recovery instructions. The issue is complete only when the failure is understood and a verified fix or clearly documented recovery path is available.

Written by the indexing model from the issue text.