Revert "Correct OnSendAddinsEnabled description"

Author: garycentric

exchange/exchange-ps/ExchangePowerShell/Set-OwaMailboxPolicy.md

@@ -1836,13 +1836,10 @@ Accept wildcard characters: False
 ```
 
 ### -OnSendAddinsEnabled
+The OnSendAddinsEnabled parameter specifies whether to enable or disable on send add-ins in Outlook on the web (add-ins that support events when a user clicks Send). Valid values are:
 
-> Applicable: Exchange Server 2016, Exchange Server 2019, Exchange Online
-
-The OnSendAddinsEnabled parameter specifies whether a mail item can be edited while an on-send add-in is processing it in Outlook on the web or the new Outlook on Windows. Valid values are:
-
-- $true: A user isn't able to edit a mail item while an on-send add-in is processing the item.
-- $false: A user is able to edit a mail item while an on-send add-in is processing the item. This is the default value.
+- $true: On send add-ins are enabled.
+- $false: On send add-ins are disabled. This is the default value.
 
 ```yaml
 Type: Boolean