The errors occur on ex. Windows11, Debian 12.6 and SuseLeap 15.6.

If changing the following line in demo read_blocking_website.tcl

`chan configure $ch -blocking 1 -buffering line -buffersize 16384 -encoding utf-8 -translation {auto crlf}`

to

`chan configure $ch -blocking 1 -buffering line -buffersize 16384 -encoding utf-8 -translation {auto crlf} -profile tcl8`

the demo works on above mentioned systems using Tcl 9.0.2 and tls2.0b2.