[Bug]: eth_getencryptionpublickey fails on v13.4.0

Nobody has claimed this yet.

**Describe the bug**

eth_getencryptionpublickey Fails on the latest version with
```
Message: Cannot read properties of null (reading 'toLowerCase')

Code: TypeError

Stack:

TypeError: Cannot read properties of null (reading 'toLowerCase')
at chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/ui-0.js:1:557249
at zu (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:200866)
at r.unstable_runWithPriority (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:220291)
at Vo (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:141687)
at Du (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:200338)
at wu (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:191916)
at chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:141909
at r.unstable_runWithPriority (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:220291)
at Vo (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:141687)
at Qo (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:141855)
at Yo (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:141790)
at mu (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:189405)
at Object.enqueueSetState (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:145763)
at y.setState (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-8.js:1:279780)
at m.loadImage (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/ui-7.js:1:336012)
```

This can be confirmed here https://docs.metamask.io/wallet/reference/json-rpc-methods/eth_getencryptionpublickey

**Steps to reproduce**

1. Go to https://docs.metamask.io/wallet/reference/json-rpc-methods/eth_getencryptionpublickey
2. Try to execute query

**Error messages or log output**

```shell

```

**Detection stage**

In production (default)

**Version**

13.4.0

**Build type**

None

**Browser**

Chrome

**Operating system**

MacOS

No repository file, test, or entry point is named. Start by reproducing the request from the linked eth_getencryptionpublickey documentation in Chrome on macOS with version 13.4.0, then locate the extension code handling this JSON-RPC method. Done means the request completes without the reported null toLowerCase error and the relevant regression is covered.

Written by the indexing model from the issue text.