Dipak C. Gajjar

This WordPress plugin is <a href="https://wordpress.org/plugins/easy-digital-downloads/" rel="ugc">Easy Digital Downloads</a> add-on/extension, adds ‘Extra note(s)’ textarea to the checkout screen for buyers to add notes about their order.
<h4>This plugin will…</h4>
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<li>Adds ‘Extra note(s)’ textarea to the checkout screen</li>
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Adds {extra_note} email tag to show ‘Extra note(s)’ data in either the standard purchase receipt or admin notificatios
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Check the <a href="https://wordpress.org/plugins/edd-extra-notes-on-checkout/screenshots/" rel="ugc">screenshots</a>.
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// This plugin doesn’t have any settings/options. Just Install, Activate, and Boom!
Follow the development of this plugin on <a href="https://github.com/dipakcg/edd-extra-notes-on-checkout" rel="nofollow ugc">GitHub</a>
P.S. It is always the best policy to open a <a href="https://wordpress.org/support/plugin/edd-extra-notes-on-checkout" rel="ugc">support thread</a> first before posting any negative review.

Easy Digital Downloads – Extra note(s) On Checkout

Easy Digital Downloads add-on/extension, adds 'Extra note(s)' textarea to the checkout screen for buyers to add notes about their order.

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affmngr

This addon allows you to integrate Sell Digital Downloads with the Affiliates Manager plugin.
When a user pay for a download on your site, this addon will check to see if the user was referred to your site by an affiliate. It will then give commission to the affiliate who referred the user.
This addon requires the <a href="https://wordpress.org/plugins/affiliates-manager/" rel="ugc">Affiliates Manager</a> and <a href="https://wordpress.org/plugins/sell-digital-downloads/" rel="ugc">Sell Digital Downloads</a> plugins.
Read the usage instructions <a href="https://wpaffiliatemanager.com/affiliates-manager-sell-digital-downloads-integration/" rel="nofollow ugc">here</a>

Affiliates Manager and Sell Digital Downloads

Process an affiliate commission via Affiliates Manager after a sell digital downloads checkout

Easy Digital Downloads – Extra note(s) On Checkout vs Affiliates Manager and Sell Digital Downloads