Perform the following steps:

1. Save the PKCS #11 module to a permanent location on your local computer
2. Select Tools > Options or select the Firefox menu and then Options
3. Once the Options page opens, select Privacy & Security
4. Scroll down to the bottom of the page and under Certificates click or tap on Security Devices…
5. Click or tap the Load button
6. Enter a name for the security module, such as "My Client Database"

   Warning: Be careful about using international characters as there is currently a bug in Firefox where international characters may cause problems.

7. Choose Browse… to find the location of the PKCS #11 module on your local computer, and then click or tap OK to confirm.

There are two environmental prerequisites for using this API:

• One or more PKCS #11 modules must be installed on the user's computer
• For each installed PKCS #11 module, there must be a native manifest file that enables the browser to locate the module.

Most probably, the user or device administrator would install the PKCS #11 module, and its installer would install the native manifest file at the same time.

However, the module and manifest can't be installed as part of the extension's own installation process.

For details about the manifest file's contents and location, see Native manifests.

pkcs11.getModuleSlots()

For each slot in a module, get its name and whether it contains a token.

pkcs11.installModule()

Installs the named PKCS #11 module.

pkcs11.isModuleInstalled()

Checks whether the named PKCS #11 module is installed.

pkcs11.uninstallModule()

Uninstalls the named PKCS #11 module.