Fix

render_books.py

@@ -88,7 +88,7 @@ def render_inline(nodes, book, chapter, out):
             n = node["id"].replace("FN", "")
             out.append('<a class="noteref" id="fnref%s_%s" href="#fn%s_%s">'
                        "<sup>%s</sup></a>" % (chapter, n, chapter, n,
-                                              esc(node.get("marker") or "*")))
+                                              esc(caller(node.get("marker")))))
         elif kind == "br":
             out.append("<br>")
         elif kind == "ref":
@@ -118,6 +118,22 @@ def render_block(block, book, chapter, out):
     out.append("</%s>\n" % tag)
 
 
+# Footnote callers arrive from the source as * † ‡ § ✡. The star is the only
+# one of them a browser may decide is an emoji: no serif font carries a glyph
+# for U+2721, so the fallback chain reaches the colour emoji font and drops a
+# purple tile into the middle of a verse. U+FE0E is the standardised way to ask
+# for the text glyph of the same character -- the symbol, not the emoji. There
+# is no separate text codepoint to switch to; this is the only lever.
+TEXT_PRESENTATION = "\ufe0e"
+EMOJI_CAPABLE = "\u2721"
+
+
+def caller(marker):
+    """A footnote marker, asked to render as text rather than as an emoji."""
+    return "".join(c + TEXT_PRESENTATION if c in EMOJI_CAPABLE else c
+                   for c in (marker or "*"))
+
+
 def render_notes(notes, chapter, book, out):
     if not notes:
         return
@@ -128,7 +144,7 @@ def render_notes(notes, chapter, book, out):
         n = (note["id"] or "").replace("FN", "")
         out.append('          <li class="note" id="fn%s_%s" data-kind="%s">'
                    % (chapter, n, note["kind"]))
-        out.append('<span class="marker">%s</span> ' % esc(note.get("marker") or "*"))
+        out.append('<span class="marker">%s</span> ' % esc(caller(note.get("marker"))))
         if note.get("ref"):
             out.append('<a class="backref" href="#fnref%s_%s">%s</a> '
                        % (chapter, n, esc(note["ref"])))