I've noticed that a small line of white pixels remains at the top and on the left of the screen while playing a file in fullscreen mode.
Actually, it is the left and top borders you can see in non-fulllscreen mode.

Is it a known bug? Is there a way to fix that?

edit: 808 build on 30 Apr 2004

You're right. It's still there. For some users it are top and left borders and for others bottom and right borders.
I use "Borderless play window" myself as a "workaround" (otherwise I will continually be annoyed with it).
(rightclick > Options > Preferences > Video > "Borderless play window")

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( http://bsplayer.com/forum/viewtopic.php?p=10638#10638 )
( http://bsplayer.com/forum/viewtopic.php?p=11358#11358 )
Checked and found still present in build 809.
(Went back to "borderless" again).

Example: full screen pasted on a blue background:

__________________
Help2Help (click) BSplayer: simply the best & most versatile (Build 1072 Dutch language here!)
When posting always mention your computer's OS and the version and build number(!) of BS.Player as used by you,
as well as - if applicable and especially when encountering problems - the type(s) of the file(s) mentioned in your post.
Private messages/Visitor messages are NOT for seeking personal help with respect to BS.Player! Instead use the forums!