[neeraj1235476]

Vt100_Output.write() is what print_formatted_text() uses for plain text, and its docstring says it removes vt100 escape codes, but it only replaces ESC. The 8-bit C1 introducers (CSI \x9b, OSC \x9d, DCS \x90, ST \x9c, ...) go straight to the terminal, and xterm and VTE-based terminals act on them in UTF-8 mode. So print_formatted_text("\x9b2J\x9b31m...") with untrusted text (a filename, a server response, output sent to a telnet/ssh client) clears the screen or changes styling. set_title() has the same gap: it strips ESC and BEL, but a \x9c in the title ends the OSC early, and anything after it is written as raw output.

write() now also replaces \x80-\x9f with ?, the same as ESC. Most text is ASCII, so an isascii() check keeps that path at a single str.replace. set_title() drops the same range. The layout Screen already shows these characters as <9b> etc., so this only brings the direct-write path in line with it. Tests are added in tests/test_vt100_output.py.