Revert "Remove FairEmail (#1270)"

This reverts commit abd2fa0ff0.

docs/assets/img/email-clients/fairemail.svg

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg width="128" height="128" version="1.1" viewBox="0 0 33.867 33.867" xmlns="http://www.w3.org/2000/svg"><defs><linearGradient id="color-1" x2="0" gradientUnits="userSpaceOnUse"><stop stop-opacity=".3" offset="0"/><stop stop-opacity="0" offset="1"/></linearGradient></defs><g transform="matrix(.7697 0 0 .7697 -1.5394 -1.5394)" font-family="none" font-size="none" font-weight="none" stroke-miterlimit="10" text-anchor="none" style="mix-blend-mode:normal"><path d="m7 43c-1.1046 0-2-0.89543-2-2v-34c0-1.1046 0.89543-2 2-2h34c1.1046 0 2 0.89543 2 2v34c0 1.1046-0.89543 2-2 2z" fill="#039be5"/><path d="m31.816 16.184h-15.632c-1.0796 0-1.9442 0.87442-1.9442 1.954l-0.0098 11.724c0 1.0796 0.87442 1.954 1.954 1.954h15.632c1.0796 0 1.954-0.87442 1.954-1.954v-11.724c0-1.0796-0.87442-1.954-1.954-1.954zm0 3.908-7.8161 4.885-7.8161-4.885v-1.954l7.8161 4.885 7.8161-4.885z" fill="none" stroke-width="0"/><path d="m33.77 18.138v11.724c0 1.0796-0.87442 1.954-1.954 1.954h-15.632c-1.0796 0-1.954-0.87442-1.954-1.954l0.0098-11.724c0-1.0796 0.86465-1.954 1.9442-1.954h15.632c1.0796 0 1.954 0.87442 1.954 1.954zm-1.954 0-7.8161 4.885-7.8161-4.885v1.954l7.8161 4.885 7.8161-4.885z" fill="#fff" stroke-width="0"/><g fill="none"><path d="m2 24c0-12.15 9.8497-22 22-22s22 9.8497 22 22-9.8497 22-22 22-22-9.8497-22-22z"/><rect x="2" y="2" width="44" height="22"/><path d="m2 24v-22h44v22z"/><path d="m2 24v-22h44v22z"/><path d="m2 24v-22h44v22z"/><path d="m2 24v-22h44v22z"/></g></g></svg>

docs/email-clients.en.md

@@ -123,6 +123,25 @@ Our recommendation list contains email clients that support both [OpenPGP](encry
         [:pg-f-droid:](https://f-droid.org/packages/com.fsck.k9){ .card-link title=F-Droid }
         [:fontawesome-brands-github:](https://github.com/k9mail/k-9/releases){ .card-link title=GitHub }
 
+## FairEmail
+
+!!! recommendation
+
+    ![FairEmail logo](assets/img/email-clients/fairemail.svg){ align=right }
+
+    **FairEmail** is a minimal, open source email app, using open standards (IMAP, SMTP, OpenPGP) with a low data and battery usage.
+
+    [:octicons-home-16: Homepage](https://email.faircode.eu){ .md-button .md-button--primary }
+    [:octicons-eye-16:](https://github.com/M66B/FairEmail/blob/master/PRIVACY.md){ .card-link title="Privacy Policy" }
+    [:octicons-info-16:](https://github.com/M66B/FairEmail/blob/master/FAQ.md){ .card-link title=Documentation}
+    [:octicons-code-16:](https://github.com/M66B/FairEmail){ .card-link title="Source Code" }
+    [:octicons-heart-16:](https://email.faircode.eu/donate/){ .card-link title=Contribute }
+
+    ??? downloads
+
+        [:fontawesome-brands-google-play:](https://play.google.com/store/apps/details?id=eu.faircode.email){ .card-link title="Google Play" }
+        [:pg-f-droid:](https://f-droid.org/packages/eu.faircode.email/){ .card-link title=F-Droid }
+
 ## Canary Mail
 
 !!! recommendation

docs/encryption.en.md

@@ -314,7 +314,7 @@ When encrypting with PGP, you have the option to configure different options in
 
     ![OpenKeychain logo](assets/img/encryption-software/openkeychain.svg){ align=right }
 
-    **OpenKeychain** is an Android implementation of GnuPG. It's commonly required by mail clients, such as [K-9 Mail](email-clients.md#k-9-mail), and other Android apps to provide encryption support. Cure53 completed a [security audit](https://www.openkeychain.org/openkeychain-3-6) of OpenKeychain 3.6 in October 2015. Technical details about the audit and OpenKeychain's solutions can be found [here](https://github.com/open-keychain/open-keychain/wiki/cure53-Security-Audit-2015).
+    **OpenKeychain** is an Android implementation of GnuPG. It's commonly required by mail clients such as [K-9 Mail](email-clients.md#k-9-mail) and [FairEmail](email-clients.md#fairemail) and other Android apps to provide encryption support. Cure53 completed a [security audit](https://www.openkeychain.org/openkeychain-3-6) of OpenKeychain 3.6 in October 2015. Technical details about the audit and OpenKeychain's solutions can be found [here](https://github.com/open-keychain/open-keychain/wiki/cure53-Security-Audit-2015).
 
     [:octicons-home-16: Homepage](https://www.openkeychain.org){ .md-button .md-button--primary }
     [:octicons-eye-16:](https://www.openkeychain.org/help/privacy-policy){ .card-link title="Privacy Policy" }

docs/tools.en.md

@@ -255,6 +255,7 @@ We [recommend](dns.md#recommended-providers) a number of encrypted DNS servers b
 - ![Kontact logo](assets/img/email-clients/kontact.svg){ .twemoji } [Kontact (Linux)](email-clients.md#kontact)
 - ![Mailvelope logo](assets/img/email-clients/mailvelope.svg){ .twemoji } [Mailvelope (PGP in standard webmail)](email-clients.md#mailvelope)
 - ![K-9 Mail logo](assets/img/email-clients/k9mail.svg){ .twemoji } [K-9 Mail (Android)](email-clients.md#k-9-mail)
+- ![FairEmail logo](assets/img/email-clients/fairemail.svg){ .twemoji } [FairEmail (Android)](email-clients.md#fairemail)
 - ![Canary Mail logo](assets/img/email-clients/canarymail.svg){ .twemoji } [Canary Mail (iOS)](email-clients.md#canary-mail)
 - ![NeoMutt logo](assets/img/email-clients/mutt.svg){ .twemoji } [NeoMutt (CLI)](email-clients.md#neomutt)