zenfone7: add Zulip support link

Change-Id: I5b400d31dd4cd7286833b3adaeb0940246bdcb80
diff --git a/_asus/zenfone7.markdown b/_asus/zenfone7.markdown
index 089d7ed..beebe28 100644
--- a/_asus/zenfone7.markdown
+++ b/_asus/zenfone7.markdown
@@ -8,6 +8,7 @@
 maintainer: Captain_Throwback
 devicetree: https://github.com/TeamWin/android_device_asus_I002D
 xdathread: "https://forum.xda-developers.com/asus-zenfone-7/development/recovery-twrp-asus-zenfone-7-series-t4161719"
+<p class="text"><a href="https://twrp.zulipchat.com/#narrow/stream/290973-support-device/topic/ASUS.20ZenFone.207">Support topic on Zulip</a></p>
 ---
 
 
@@ -24,7 +25,7 @@
 
 
 {% include twrpinstall.html %}
-<b>NOTE:</b> This will only install TWRP to the current slot!!
+<b>NOTE:</b> By default, only the current slot will be flashed. Checking the \"Flash to both slots\" box will flash to both the active and inactive slots.
 
 
 <html>