docs: add certificate install instructions

docs/src/SUMMARY.md

@@ -11,6 +11,7 @@
   - [Setup VSCode Remote](./how-to/vscode.md)
   - [Change the username](./how-to/change-username.md)
   - [Setup Nix Flakes](./how-to/nix-flakes.md)
+  - [Install MSIXBundle Certificate](./how-to/install-msixbundle-certificate.md)
 - [Troubleshooting](./troubleshooting/README.md)
   - [Recovery Shell](./troubleshooting/recovery-shell.md)
 

docs/src/how-to/install-msixbundle-certificate.md

@@ -0,0 +1,21 @@
+# Install MSIXBundle Certificate
+
+To use the `.msixbundle` launcher some systems need to install the certificate
+for it. The certificate is included in the launcher and can be accessed from
+it's properties. The certificate needs to be installed in the `Trusted People`
+certificate store on the local machine which requires administrator privileges.
+
+## Step by step instructions
+
+1. Open `.msixbundle` files __properties__
+2. Select __Digital Signatures__ tab
+3. Select signature named `nzbr`
+4. Click __details__
+5. Click __View Certificate__
+6. Click __Install Certificate__
+7. Select `Local Machine` and click __Next__
+8. Select `Place all certificates in the following store` and click __Browse__
+9. Select `Trusted People` from the list and click __OK__
+10. Click __Next__ and then __Finish__
+
+You should now be able to use the `.msixbundle` launcher.