diff --git a/Debugging-PDF.js.md b/Debugging-PDF.js.md
index fc5a187..a53a8d2 100644
--- a/Debugging-PDF.js.md
+++ b/Debugging-PDF.js.md
@@ -16,7 +16,6 @@ PDF.js has several special URL parameters to alter how PDF.js works and to enabl
 * `disableRange=true` - Disables HTTP range requests when fetching the document.
 * `disableStream=true` - Disables streaming when fetching the document.
 * `disableAutoFetch=true` - Disables auto fetching of the document; only gets necessary data to display the current view. *Note:* streaming also needs to be disabled for this to have any effect. 
-* `useOnlyCssZoom=true` - Disables re-rendering of pages and uses CSS zooming instead.
 * `verbosity=[0|1|5]` - Specifies the verbosity level of console messages. 0 = only errors, 1 = warnings and errors, 5 = warnings, errors and information messages.
 * `locale=[en-US|...]` - Specifies which language to use in the viewer UI. For a list of the available locales, see https://github.com/mozilla/pdf.js/tree/master/l10n.