proc subtagDecode {text} {
      set url ""
      regsub -all {\.([0-9a-fA-F][0-9a-fA-F])} $text {[format %c 0x\1]} text
      set text [subst $text]
      regsub -all "\r\n" $text "\n" text
      foreach byte [split [encoding convertto "utf-8" $text] ""] {
        scan $byte %c i
        if { $i < 33 } {
          append url [format %%%02X $i]
        } else {
          append url $byte
        }
      }
      return [string map {% .} $url]
    }