When using a BEGIN/END block, the "Insert Semicolons" feature adds a semicolon after "END" command, but not after the "BEGIN" command.

One reason why this should be done, is the use of the THROW statement, which requires the previous statement to be terminated with a semicolon.

Technically it is still runnable code, but, SSMS (as of version 18.8) sees it as a syntax error (see screenshot).

I don't know which is the appropriate fix...waiting for SSMS to fix the syntax error it shows (but I doubt they will since the non-use of semicolons is deprecated), or if it's appropriate for this feature to add them after BEGIN statements.

Sample:
BEGIN
THROW 51000, 'Test', 1;
END;