Signing a message via the website adds extra dashes in edge case

I just signed a message via the website that contained a variation of the following:

```
-----BEGIN X509 CRL-----
00000000000000000000
00000000000000000000
00000000000000000000
00000000000000000000
-----END X509 CRL-----
```

After I signed the message, I saw this:

```
- -----BEGIN X509 CRL-----
00000000000000000000
00000000000000000000
00000000000000000000
00000000000000000000
- -----END X509 CRL-----
```

Notice the extra dash and space on the BEGIN / END line. That addition essentially breaks the format that OpenSSL is expecting. I didn't see any of these added anywhere else in the message.

Start by reproducing the issue in the website's message-signing flow with the X509 CRL example shown in the report, then compare the signed output with the original delimiters. Done means the BEGIN and END lines retain their original dashes and spacing, so the resulting format remains acceptable to OpenSSL.

Written by the indexing model from the issue text.