blob_appendf(pOut, "%s\n", zNonce);
  }
  blob_reset(&bIn);
  return isErr;
}

/*
** Legacy impl of /pikchrshow. pikchrshow_page() will delegate to
** this one if the "legacy" or "ajax" request arguments are set.
**
** A pikchr code editor and previewer, allowing users to experiment
** with pikchr code or prototype it for use in copy/pasting into forum
** posts, wiki pages, or embedded docs. This version of pikchrshow
** uses JavaScript to send pikchr code to the server for
** processing. The newer /pikchrshow applications runs pikchr on the
** client machine, without the need for back-and-forth network
** traffic.



*/
void pikchrshowcs_page(void){
  const char *zContent = 0;
  int isDark;              /* true if the current skin is "dark" */
  int pikFlags =
    PIKCHR_PROCESS_DIV
    | PIKCHR_PROCESS_SRC

** WEBPAGE: pikchrshow
**
** A pikchr code editor and previewer, allowing users to experiment
** with pikchr code or prototype it for use in copy/pasting into forum
** posts, wiki pages, or embedded docs. This version of pikchrshow
** uses WebAssembly to run entirely in the client browser, without a
** need for back-and-forth client/server traffic to perform the
** rendering. The "legacy" version of this application, which sends
** all input to the server for rendering, can be accessed by adding
** the "legacy" URL argument.
**
** It optionally accepts a p=pikchr-script-code URL parameter or POST
** value to pre-populate the editor with that code.
*/
void pikchrshow_page(void){
  const char *zContent = 0;

  if(P("legacy") || P("ajax")){
    pikchrshowcs_page();
    return;

  if(!zContent){
    zContent = "arrow right 200% \"Markdown\" \"Source\"\n"
      "box rad 10px \"Markdown\" \"Formatter\" \"(markdown.c)\" fit\n"
      "arrow right 200% \"HTML+SVG\" \"Output\"\n"
      "arrow <-> down from last box.s\n"
      "box same \"Pikchr\" \"Formatter\" \"(pikchr.c)\" fit\n";
  }
  /* Wasm load/init progress widget... */
  CX("<div class='emscripten'>"); {
    CX("<figure id='module-spinner'>");
      CX("<div class='spinner'></div>");
      CX("<div class='center'><strong>Initializing app...</strong></div>");
      CX("<div class='center'>");
        CX("On a slow internet connection this may take a moment.  If this ");
        CX("message displays for \"a long time\", intialization may have ");
        CX("failed and the JavaScript console may contain clues as to why. ");
      CX("</div>");
      CX("<div><a href='?legacy'>Switch to legacy mode</a></div>");
    CX("</figure>");
    CX("<div class='emscripten' id='module-status'>Downloading...</div>");
    CX("<progress value='0' max='100' id='module-progress' hidden='1'>"
       "</progress>");
  } CX("</div><!-- .emscripten -->");
  /* Main view... */
  CX("<div id='view-split' class='app-view initially-hidden'>"); {
    CX("<div class='fieldset options collapsible'>"); {
      CX("<span class='legend'><span>Options</span></span>");
      CX("<div>");
      CX("<span class='labeled-input'>");
        CX("<input type='checkbox' id='opt-cb-sbs' ");
        CX("data-csstgt='#main-wrapper' ");

        CX("<a href='?legacy'>Legacy mode</a>");
      CX("</span>");
      CX("</div><!-- options wrapper -->");
    } CX("</div><!-- .fieldset -->");
    CX("<div id='main-wrapper' class=''>"); {
      CX("<div class='zone-wrapper input'>"); {
        CX("<textarea id='input'");
          CX("placeholder='Pikchr input. Ctrl-enter/shift-enter runs it.'>");
          CX("/**\n");
          CX("  Use ctrl-enter or shift-enter to execute\n");
          CX("  pikchr code. If only a subset is currently\n");
          CX("  selected, only that part is evaluated.\n*/\n");
        CX("%s</textarea>",zContent/*safe-for-%s*/);
        CX("<div class='button-bar'>");
          CX("<button id='btn-render'>Render</button>");