uepselon

This plugin offers your blog visitors a <a href="http://www.foxload.com/firefox-download/" title="firefox download" rel="nofollow ugc">firefox download</a> button in different formats and colors on the sidebar.
Different banner formats and colors are included. The plugin use the wordpress locale settings for proper language versions of firefox.
You can place firefox buttons as widget and if your theme does not support widgets, you can place this <code><?php if(function_exists('get_foxload_button'))get_foxload_button(); ?></code> php code at the preferred position in your template.

Foxload Firefox Download

Offers your blog visitors a firefox download button in different formats and colors on the sidebar.

pushdytech

<a href="https://www.pushdy.vn" rel="nofollow ugc">Pushdy</a> is an easy way to increase user engagement. Use Pushdy to send visitors targeted push notifications so they keep coming back. It takes just a few minutes to install.
After setup, your visitors opt-in to receive push notifications when you publish a new post. Visitors receive these notifications even after they’ve left your website, thus driving re-engagement.
You can configure notification delivery at preset intervals, create user segments, and customize the opt-in process for visitors.
<h4>Features</h4>
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Supports Chrome (Desktop & Android), Safari (Mac OS X), Microsoft Edge (Desktop & Android), Opera (Desktop & Android) and Firefox (Desktop & Android) on HTTPS sites.
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<li>
Automatic Notifications – Send notifications to followers every time you publish a new post. Or set up a reminder that gets automatically sent to them if they haven’t visited for a few days.
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Targeting Segments – Send notifications to specific visitors based on language, number of times they’ve visited your blog, or even set up your own user attributes that you can target.
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Opt-In Customization – Choose when and how to ask your visitors to opt-in to browser notifications. Customize the prompt they first see.
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Real Time Analytics – See your notifications being delivered in real time, and watch them as they convert into visitors.
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A/B Testing – Try out different messages to a smaller set of your visitors to figure out which messages are more effective and then send the more effective message to the rest of your visitors!
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Scheduled Notifications – Schedule notifications to be delivered in the future, based on a user’s time zone, or even based on the same time of day they last visited your website.
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</ul>

Pushdy – Web Push Notifications

Increase engagement and drive more repeat traffic to your WordPress site with desktop push notifications. Now supporting Chrome, Firefox, and Safari.

Foxload Firefox Download vs Pushdy – Web Push Notifications