The difference between MySQL left join and left outer join

Let’s talk about the conclusion first:
the results of left join and left outer join are consistent.
I don’t know how the masters tested it. It is said on the Internet that the two are different. My A and B tables both have duplicate data. Why are the results the same?

Table A

Table B

left join

SELECT ta.*,tb.Result ResultB
FROM TableA ta
LEFT JOIN TableB tb ON ta.Result = tb.Result;

left outer join

SELECT ta.*,tb.Result ResultB
FROM TableA ta
LEFT outer JOIN TableB tb ON ta.Result = tb.Result;

According to the following MySQL official document (page 2664), outer join exists for the compatibility of some third-party programs.

Microsoft's explanation:
https://learn.microsoft.com/zh-cn/mem/configmgr/develop/core/understand/sqlviews/sql-statement-reference-configuration-manager-reports