Error: Call to a member function getValues() on null (adminhtml event - adminhtml_block_salesrule_actions_prepareform)

[MagePsycho]

In Magento 2.1, adminhtml_block_salesrule_actions_prepareform event is not working

<event name="adminhtml_block_salesrule_actions_prepareform">
        <observer name="magepsycho_cartrule_adminhtml_block_salesrule_actions_prepareform" instance="MagePsycho\Cartrule\Observer\AdminhtmlBlockSalesruleActionsPrepareform" />
    </event>

which results in

Error: Call to a member function getValues() on null in app/code/MagePsycho/Cartrule/Observer/AdminhtmlBlockSalesruleActionsPrepareform.php on line 41

This used to work in prior to 2.1 and similar approach in Magento 1 as well.
Have Magento2 team changed the way of injecting custom form fields for Cart Rules?

[andimov]

@MagePsycho
Thank you for reporting!
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[andimov]

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