bug#38921: Descriptions of elisp function 'modify-frame-parameters frame alist' in the lispref manual.

[Eli Zaretskii]

> From: Takesi Ayanokoji <ayanokoji.takesi@gmail.com>
> Date: Sun, 5 Jan 2020 01:47:41 +0900
> 
> Some parameters are only meaningful for frames on certain kinds of display 
> (@pxref{Frames}).  If @var{alist}
> includes parameters that are not meaningful for the @var{frame}'s display, 
> this function will change its value
> in the frame's parameter list, but will otherwise ignore it.
> ---
> 
> So, my question is,
> Either 'not' or 'otherwise' is not necessary, isn't it?

No, both are necessary.  The "otherwise" part means "other than
changing the value of the parameter".