symbols display wrong in `screen` - ascii or utf

Question

I don't know since when and why :

$ mkdir -p a/b/c x/y/{1,2,3}
$ tree
.
├── a
│   └── b
│       └── c
└── x
    └── y
        ├── 1
        ├── 2
        └── 3

8 directories, 0 files

when I run screen, displays symbols full of question marks:

$ screen
<-- screen starts... -->
$ tree
.
��� a
�   ��� b
�       ��� c
��� x
    ��� y
        ��� 1
        ��� 2
        ��� 3

8 directories, 0 files

Similarly for utf characters.

Even if I move away my .screenrc (e.g. with mv -v ~/.screenrc{,.bak} ) it's still strange characters set.

It happens on screen on my main user, on root user, but on my secondary user it does not. On this one characters work properly in screen. And it's not .screenrc as I played with it.

Updates:

Re: $TERM - seems unrelated

• without screen: TERM==xterm-256color
• user A inside screen: TERM==screen.xterm-256color and display incorrectly
• user B inside screen: TERM==screen.xterm-256color and display correctly

Re: defutf8 on - does something

After adding defutf8 on in .screenrc there is now mix ;p some symbols work some don't, example :

$ tree
.
├── a
│�� └── b
│��     └── c
└── x
    └── y
        ├── 1
        ├── 2
        └── 3

8 directories, 0 files

Answer 1

Thanks to comments in my original question, they helped me to narrow troubleshooting and find that this one line in my ~/.bashrc is the cause - locale staff I guess:

export LC_PAPER=a4

with this line, e.g. tree displays correctly without screen but incorrectly inside screen.

After removing this line from .bashrc it looks good again.