All error and debug messages are by default logged to the JS category of the Error Console. The Error Console is accessible in the Thunderbird menu under Tools > Developer Tools > Error Console (in older versions under Tools > Error Console) or by pressing the keyboard shortcut Ctrl+Shift+J.

By default only errors are logged. Debug messages can be enabled in the advanced preferences of the add-on.

If you do not see any messages, make sure that Show Content Messages is enabled in the gear icon on the top right.

The messages are also shown in the developer tools for add-ons (see also https://extensionworkshop.com/documentation/develop/debugging/). Note however that the log messages of the experiments (e.g. the DNS resolvers) do not show up there. They will only show up in the Error Console and in the debugger for Thunderbird itself (which must also be used to debug the experiments code).

To open the developer tools go to the Add-ons Manager, click on the gears icon in the right top and select Debug Add-ons. In the debugging tab that opens click the Inspect button under the entry for the DKIM Verifier add-on.

The add-on contains some hidden options, that can not be set via the options GUI dialog of the add-on, but are mentioned in the documentation.

To set a hidden option do the following:

1. Open the add-ons manager
2. Click the gear in the top right and select "Debug Add-ons"
3. Click the "Inspect" button of the DKIM Verifier (a tab should open with something similar as described at https://extensionworkshop.com/documentation/develop/debugging/)
4. In the top, click on Console
5. In the console, enter and execute await (await import("../modules/preferences.mjs.js")).default.setValue("<name>", <value>)
   • Replace <name> and <value>
   • E.g. to set dns.jsdns.autoResetServerAlive to true: await (await import("../modules/preferences.mjs.js")).default.setValue("dns.jsdns.autoResetServerAlive", true)

The options can be set via Thunderbird's config editor.

Note that besides the account specific options, all do start with extensions.dkim_verifier.. The documentation however provides the names like they are needed for newer add-on versions. You therefore need to prefix them yourself. E.g. instead of dns.jsdns.autoResetServerAlive, use extensions.dkim_verifier.dns.jsdns.autoResetServerAlive.

Use the following preferences to control debugging in detail. Note that these may change in the future.

This can also be set through the add-ons option dialog.

The default. Overall log level is set to "Error". This means that logging messages with a lower level than "Error" are not shown.

Overall log level is set to "All". Use extensions.dkim_verifier.logging.console and extensions.dkim_verifier.logging.dump to set the log level in detail.

Log level for the Error Console. Available log levels are "Fatal", "Error", "Warn", "Info", "Config", "Debug", "Trace", "All".

Default is "Debug".

Removed in 4.0.0.

Log level for the native console. Available log levels are "Fatal", "Error", "Warn", "Info", "Config", "Debug", "Trace", "All".

Default is "Debug".

Removed in 4.0.0.

The default.

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