--- a/devtools/client/webconsole/new-console-output/test/mochitest/browser.ini
+++ b/devtools/client/webconsole/new-console-output/test/mochitest/browser.ini
@@ -15,17 +15,17 @@ support-files =
   test_bug_770099_violation.html
   test_bug_770099_violation.html^headers^
   test_console_csp_ignore_reflected_xss_message.html
   test_console_csp_ignore_reflected_xss_message.html^headers^
   test_hpkp-invalid-headers.sjs
   test_hsts-invalid-headers.sjs
   test-autocomplete-in-stackframe.html
   test-batching.html
-  test-bug_923281_console_log_filter.html
+  test-bug_923281_console_filename_filter.html
   test-bug_923281_test1.js
   test-bug_923281_test2.js
   test-console-trace-duplicates.html
   test-bug-585956-console-trace.html
   test-bug-599725-response-headers.sjs
   test-bug-601177-log-levels.html
   test-bug-601177-log-levels.js
   test-bug-630733-response-redirect-headers.sjs
@@ -270,16 +270,17 @@ skip-if = (e10s && debug) || (e10s && os
 [browser_webconsole_duplicate_errors.js]
 [browser_webconsole_errors_after_page_reload.js]
 [browser_webconsole_eval_in_debugger_stackframe.js]
 [browser_webconsole_eval_in_debugger_stackframe2.js]
 [browser_webconsole_execution_scope.js]
 [browser_webconsole_external_script_errors.js]
 [browser_webconsole_file_uri.js]
 skip-if = true #	Bug 1404382
+[browser_webconsole_filename_filters.js]
 [browser_webconsole_filter_scroll.js]
 [browser_webconsole_filters.js]
 [browser_webconsole_filters_persist.js]
 [browser_webconsole_highlighter_console_helper.js]
 [browser_webconsole_history_arrow_keys.js]
 [browser_webconsole_hpkp_invalid-headers.js]
 [browser_webconsole_hsts_invalid-headers.js]
 [browser_webconsole_iframe_wrong_hud.js]

rename from devtools/client/webconsole/test/browser_webconsole_log_file_filter.js
rename to devtools/client/webconsole/new-console-output/test/mochitest/browser_webconsole_filename_filters.js
--- a/devtools/client/webconsole/test/browser_webconsole_log_file_filter.js
+++ b/devtools/client/webconsole/new-console-output/test/mochitest/browser_webconsole_filename_filters.js
@@ -1,83 +1,117 @@
 /* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
 /* vim: set ft=javascript ts=2 et sw=2 tw=80: */
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
-// Tests that the text filter box works to filter based on filenames
-// where the logs were generated.
+// Tests that the text filter box works to filter based on filenames where the
+// logs were generated. These tests are for bug 923281 and bug 1448553.
 
 "use strict";
 
-const TEST_URI = "http://example.com/browser/devtools/client/webconsole/" +
-                 "test/test-bug_923281_console_log_filter.html";
-
 var hud;
 
-add_task(function* () {
-  yield loadTab(TEST_URI);
+// Testcase 1: Test filtering outputs with an ASCII filename when searching a
+// keyword.
+
+const TEST_ASCII_URI = "http://example.com/browser/devtools/client/" +
+                         "webconsole/new-console-output/test/mochitest/" +
+                         "test-bug_923281_console_filename_filter.html";
+
+function testFilteringOutputsWithAsciiFilename() {
+  const numLogs = findMessages(hud, "").length;
+
+  is(numLogs, 3, "There are 3 logs in total.");
+
+  is(findMessages(hud, "random").length, 1,
+     "the log not containing string \"random\" are hidden");
+
+  is(findMessages(hud, "test2.js").length, 2,
+     "show only logs containing string " +
+       "\"test2.js\" or log nodes created from files with filename " +
+       "containing \"test2.js\" as substring.");
+
+  is(findMessages(hud, "test1").length, 2,
+     "show only logs containing string " +
+       "\"test1\" or log nodes created from files with filename " +
+       "containing \"test1\" as substring.");
+}
+
+// Testcase 2: Test filtering outputs in a Unicode filename when searching a
+// keyword.
+
+// There are three hanzi:
+// The `HANZI_1` is used both as a Unicode filename and a console log.
+// The `HANZI_2` is used only as a console log.
+
+// The value of the `uri` property is used as a URI-encoded form in a URL.
+// The value of the `js` is used as a Javascript string form.
+const HANZI_1 = {
+  uriEncoded: "%E6%B8%AC",
+  js: "\u6e2c",
+  escapedJs: "\\u6e2c",
+};
+
+// A hanzi in two forms.
+// The value of the `js` is used to in Javascript string.
+const HANZI_2 = {
+  js: "\u8a66",
+  escapedJs: "\\u8a66",
+};
 
-  hud = yield openConsole();
-  yield consoleOpened();
+const RESPONSE_DATA = `<!DOCTYPE html
+><meta charset="utf-8"
+><title>Test for filtering a Unicode filename</title
+><script>
+console.log("This log has no Unicode character.");
+console.log("This log has unicode: ${HANZI_1.escapedJs}");
+console.log("This log has unicode: ${HANZI_2.escapedJs}");
+</script>`;
+
+// Create an HTTP server to simulate a response for the a URL request
+// containing a Unicode filename.
+const httpServer = createTestHTTPServer();
+httpServer.registerContentType("html", "text/html");
+httpServer.registerPathHandler(`/${HANZI_1.uriEncoded}.html`,
+  function(request, response) {
+    response.setStatusLine(request.httpVersion, 200, "OK");
+    response.write(RESPONSE_DATA);
+  }
+);
+
+// The file suffix and the URL path used to simulate a URL request containing a
+// Unicode filename.
+const TEST_URI_ENCODED_URL = "http://localhost:" +
+                                httpServer.identity.primaryPort + "/" +
+                                HANZI_1.uriEncoded + ".html";
 
-  testLiveFilteringOnSearchStrings();
+function testFilteringOutputsWithUnicodeFilename() {
+  const numLogs = findMessages(hud, "").length;
+
+  is(numLogs, 3, "There are 3 logs in total.");
+
+  is(findMessages(hud, HANZI_1.js).length, numLogs,
+       "No log should be hidden, " +
+         "because the searched hanzi is included in the filename of " +
+         "all the logs");
+
+  is(findMessages(hud, HANZI_2.js).length, 1,
+       "Only one log should be shown, " +
+          "because all the other logs don't include the searched hanzi.");
+
+  is(findMessages(hud, HANZI_1.uriEncoded).length, 0,
+       "The filename is displayed as Unicode, " +
+          "and shouldn't be searched with a URI-encoded string.");
+}
+
+add_task(async function() {
+  // Testcase 1: Test filtering logs with an ASCII filename.
+  hud = await openNewTabAndConsole(TEST_ASCII_URI);
+  testFilteringOutputsWithAsciiFilename();
+
+  // Testcase 2: Test filtering logs with a URI-encoded filename.
+  hud = await openNewTabAndConsole(TEST_URI_ENCODED_URL);
+  testFilteringOutputsWithUnicodeFilename();
 
   hud = null;
 });
 
-async function consoleOpened() {
-  await ContentTask.spawn(gBrowser.selectedBrowser, null, function() {
-    content.console.log("sentinel log");
-  });
-  return waitForMessages({
-    webconsole: hud,
-    messages: [{
-      text: "sentinel log",
-      category: CATEGORY_WEBDEV,
-      severity: SEVERITY_LOG
-    }],
-  });
-}
-
-function testLiveFilteringOnSearchStrings() {
-  is(hud.outputNode.children.length, 4, "number of messages");
-
-  setStringFilter("random");
-  is(countMessageNodes(), 1, "the log nodes not containing string " +
-      "\"random\" are hidden");
-
-  setStringFilter("test2.js");
-  is(countMessageNodes(), 2, "show only log nodes containing string " +
-      "\"test2.js\" or log nodes created from files with filename " +
-      "containing \"test2.js\" as substring.");
-
-  setStringFilter("test1");
-  is(countMessageNodes(), 2, "show only log nodes containing string " +
-      "\"test1\" or log nodes created from files with filename " +
-      "containing \"test1\" as substring.");
-
-  setStringFilter("");
-  is(countMessageNodes(), 4, "show all log nodes on setting filter string " +
-      "as \"\".");
-}
-
-function countMessageNodes() {
-  let outputNode = hud.outputNode;
-
-  let messageNodes = outputNode.querySelectorAll(".message");
-  let displayedMessageNodes = 0;
-  let view = hud.iframeWindow;
-  for (let i = 0; i < messageNodes.length; i++) {
-    let computedStyle = view.getComputedStyle(messageNodes[i]);
-    if (computedStyle.display !== "none") {
-      displayedMessageNodes++;
-    }
-  }
-
-  return displayedMessageNodes;
-}
-
-function setStringFilter(value) {
-  hud.ui.filterBox.value = value;
-  hud.ui.adjustVisibilityOnSearchStringChange();
-}
-

rename from devtools/client/webconsole/new-console-output/test/mochitest/test-bug_923281_console_log_filter.html
rename to devtools/client/webconsole/new-console-output/test/mochitest/test-bug_923281_console_filename_filter.html

--- a/devtools/client/webconsole/test/browser.ini
+++ b/devtools/client/webconsole/test/browser.ini
@@ -117,19 +117,16 @@ support-files =
   test-repeated-messages.html
   test-result-format-as-string.html
   test-trackingprotection-securityerrors.html
   test-webconsole-error-observer.html
   test_bug_770099_violation.html
   test_bug_770099_violation.html^headers^
   test-autocomplete-in-stackframe.html
   testscript.js
-  test-bug_923281_console_log_filter.html
-  test-bug_923281_test1.js
-  test-bug_923281_test2.js
   test-bug_939783_console_trace_duplicates.html
   test-bug-952277-highlight-nodes-in-vview.html
   test-bug-609872-cd-iframe-parent.html
   test-bug-609872-cd-iframe-child.html
   test-bug-989025-iframe-parent.html
   test-bug_1050691_click_function_to_source.html
   test-bug_1050691_click_function_to_source.js
   test-console-api-stackframe.html
@@ -360,17 +357,16 @@ skip-if = (os == 'linux' && bits == 32 &
 [browser_webconsole_split_focus.js]
 [browser_webconsole_split_persist.js]
 [browser_webconsole_trackingprotection_errors.js]
 tags = trackingprotection
 skip-if = (os == 'win' && bits == 64) # Bug 1390001
 [browser_webconsole_view_source.js]
 skip-if = (os == 'win' && bits == 64) # Bug 1390001
 [browser_webconsole_reflow.js]
-[browser_webconsole_log_file_filter.js]
 [browser_webconsole_expandable_timestamps.js]
 [browser_webconsole_autocomplete_accessibility.js]
 [browser_webconsole_autocomplete_in_debugger_stackframe.js]
 [browser_webconsole_autocomplete_popup_close_on_tab_switch.js]
 [browser_webconsole_autocomplete-properties-with-non-alphanumeric-names.js]
 [browser_console_hide_jsterm_when_devtools_chrome_enabled_false.js]
 [browser_console_history_persist.js]
 [browser_webconsole_output_01.js]

deleted file mode 100644
--- a/devtools/client/webconsole/test/test-bug_923281_console_log_filter.html
+++ /dev/null
@@ -1,12 +0,0 @@
-<!DOCTYPE HTML>
-<html dir="ltr" xml:lang="en-US" lang="en-US">
-  <head>
-    <meta charset="utf-8">
-    <title>Console test</title>
-    <!-- Any copyright is dedicated to the Public Domain.
-       - http://creativecommons.org/publicdomain/zero/1.0/ -->
-    <script type="text/javascript" src="test-bug_923281_test1.js"></script>
-    <script type="text/javascript" src="test-bug_923281_test2.js"></script>
-  </head>
-  <body></body>
-</html>

deleted file mode 100644
--- a/devtools/client/webconsole/test/test-bug_923281_test1.js
+++ /dev/null
@@ -1,7 +0,0 @@
-/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
-/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
-/* Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/ */
-
-console.log("Sample log.");
-console.log("This log should be filtered when filtered for test2.js.");

deleted file mode 100644
--- a/devtools/client/webconsole/test/test-bug_923281_test2.js
+++ /dev/null
@@ -1,8 +0,0 @@
-/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
-/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
-/* Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/ */
-
-"use strict";
-
-console.log("This is a random text.");