Issue with Mail.app rule AppleScript when script is a symbolic link

Hi All,

I found a very weird bug when using an AppleScript trigger for a Mail.app rule:

If the script inside “~/Library/Application\ Scripts/com.apple.mail/” is a symlink to an .scpt file
when an email is received, the rule script is not applied to the latest email, but to the one before it.

However if I select a message, right-click and “Apply Rules”, then the rule is applied to the right email.
Also, if I replace the symlink by a hard copy, the behavior is back to normal.

Anyone has an idea of where this comes from, if this is fixable, or where I should report that?

Thanks,
Aurel

More context

I am defining an AppleScript to be triggered on “Every Message” rule (I haven’t tried with a different type of rule though).

Here is a demo script to reproduce my issue :

using terms from application "Mail"
	
	-- Function applied to each mail when rule is triggered
	on perform mail action with messages theMessages for rule theRule
		try
			parseMessages(theMessages)
		on error errMsg number errNum
			display dialog "Error: " & errMsg & " (Code: " & errNum & ")" buttons {"OK"} default button 1 with icon caution
		end try
	end perform mail action with messages
	
	on parseMessages(theMessages)
		-- Prompt user when more then 3 messages are selected	
		set messagesCount to (count of theMessages)
		if messagesCount > 3 then if button returned of (display alert "Apply rule to " & messagesCount & " messages?" as critical buttons {"Apply", "Cancel"} default button 2) is "Cancel" then return
		-- Display message information
		repeat with msg in theMessages
			display dialog "Title: " & subject of msg as string
		end repeat
		
	end parseMessages
	
end using terms from

As this script is part of a global project:
The source is located in ~/projects/email_parsing/

If I run the following and use “mac_mail_rule_demo” the rule is not applied to incoming messages but to the last one arrived before.

ln -s ~/projects/email_parsing/mac_mail_rule_demo.scpt ~/Library/Application\ Scripts/com.apple.mail/

If I run the following then the behavior is back to normal:

cp -f ~/projects/email_parsing/mac_mail_rule_demo.scpt ~/Library/Application\ Scripts/com.apple.mail/

I am on M4 pro, macOS Tahoe Version 26.5.1 (25F80)
Mail.app Version 16.0 (3864.600.51.1.1)

Also, my mailbox account is an IMAP Microsoft Exchange one