Quoting from the first message:

> I don't know precisely what condition needs to be meet for trigger the
> bug.  But I think this is triggered when the width of the text area of
> window in character is a fraction.  For example, my window is 1366px
> width, each character takes 8px; so my window is 170.75 characters
> width, and this triggers the bug.

In the above circumstance, (window-max-chars-per-line) returns 170.  But
writing 170 characters (my font is monospace, of course) causes the last
characters to be obscured by the truncation glyph.

FYI, I used the '(insert (make-string (window-max-chars-per-line) ?\s))'
to insert spaces.

I'll dig into the 'window-max-chars-per-line' definition and report if I
find something suspicious.

-- 
Akib Azmain Turja, GPG key: 70018CE5819F17A3BBA666AFE74F0EFA922AE7F5
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