The API library could not connect to FireShot.
Please make sure you've got everything set up:

1. The FireShot extension should be installed and enabled.

Depending on your browser, please navigate to one of the following links:

• Chrome and Chromium-based browsers: https://chrome.google.com/webstore/detail/take-webpage-screenshots/mcbpblocgmgfnpjjppndjkmgjaogfceg
• Firefox: https://addons.mozilla.org/firefox/addon/fireshot
• Opera: https://addons.opera.com/extensions/details/capture-webpage-screenshot-fireshot

2. Locate the "FireShot API" checkbox and check it:

Please see a full how-to here: https://getfireshot.com/enable_api.php

3. Reload the target page.

Actually this is requred only for those pages, that have been opened before you've enabled the API.