Is your feature request related to a problem? Please describe.
When working with a big piece of text, I sometimes scroll down and copy some text into another tab. When switching back to the first tab, both the input and the output pane is back on top. So I don't know where I was working just now.

Describe the solution you'd like
After tab switching, scroll position should be remembere

I'm building a CLI similar to dotnet where each subcommand has an optional argument. The top level help message looks like the following:

Commands:
  install <path-to-config>      ...
  uninstall <path-to-config>    ...
  start <path-to-config>        ...
  stop <path-to-config>         ...
  restart <path-to-config>      ...
  status <path-to-config>       ...
  test <path-to-con

Everything in diagrams.css should be scoped to some wrapping css class, because as is it cannot be bundled with the rest of an app's css because of styles like this:

div {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

svg {
    width: 100%;
}

Curre

This is related to #410 and #859, we currently only support a limited subset of possible values for RDATE, but we should support all the parameters in RDATE, the grammar for which is set out in RFC 5545:

       rdate      = "RDATE" rdtparam ":" rdtval *("," rdtval) CRLF

       rdtparam   = *(
                  ;
                  ; T