Open PDF file with open parameter(#view=Fit) doesn't work the first time

Description
When using WebView2 to open PDF file, it only supports to set fit width and set fit both in toolbar.

But in our project,
we need to support to set fit height, and we uses the opening paramter "#view=FitV" to implement it.
However, "#view=FitV" doesn't work the first time.

Repro Steps

1. Open a PDF file(e.g. 1.pdf) in WebView2
2. Reopen 1.pdf with #view=FitV, after this step, the setting fit height doesn't work.
3. Reopen 1.pdf with #view=FitV again, after this step, the setting fit height works.

But if we open another PDF with #view=FitV, it works.

1. Open a PDF file(e.g. 1.pdf) in WebView2
2. Open another PDF file(e.g. 2.pdf) with #view=FitV, after this step, the setting fit height works.

Why reopen the PDF file with #view=FitV first time, it doesn't work?

AB#39611010