diff --git a/hgext3rd/copytrace.py b/hgext3rd/copytrace.py
--- a/hgext3rd/copytrace.py
+++ b/hgext3rd/copytrace.py
@@ -75,7 +75,7 @@
         ("", "drafttrace", None,
          _("enable copytracing for draft branches.")))
 
-    # With experimental.disablecopytrace=True there can be cryptic merge errors.
+    # With experimental.copytrace=off there can be cryptic merge errors.
     # Let"s change error message to suggest re-running the command with
     # enabled copytracing
     filemerge._localchangedotherdeletedmsg = _(
@@ -105,10 +105,10 @@
         # even with disabled copytracing, so we don't want to log it.
         if orig != fco.path() and fco.cmp(fcd):
             # copytracing was in action, let's record it
-            if not repo.ui.configbool("experimental", "disablecopytrace"):
-                msg = "success"
+            if repo.ui.config('experimental', 'copytrace') == 'on':
+                msg = 'success (fastcopytracing)'
             else:
-                msg = "success (fastcopytracing)"
+                msg = 'success'
 
             try:
                 destctx = _getctxfromfctx(fcd)
@@ -128,8 +128,7 @@
 
 def _runcommand(orig, lui, repo, cmd, fullargs, ui, *args, **kwargs):
     if "--tracecopies" in fullargs:
-        ui.setconfig("experimental", "disablecopytrace",
-                     False, "--tracecopies")
+        ui.setconfig('experimental', 'copytrace', 'on', '--tracecopies')
     return orig(lui, repo, cmd, fullargs, ui, *args, **kwargs)
 
 def _amend(orig, ui, repo, old, extra, pats, opts):
@@ -325,7 +324,7 @@
 
     """
 
-    if not repo.ui.configbool("experimental", "disablecopytrace"):
+    if repo.ui.config('experimental', 'copytrace') == 'on':
         # user explicitly enabled copytracing - use it
         return orig(repo, cdst, csrc, base)
 
@@ -335,7 +334,7 @@
     # If base, source and destination are all draft branches, let's use full
     # copytrace for increased capabilities since it will work fast enough
     if _isfullcopytraceable(repo.ui, cdst, base):
-        configoverrides = {('experimental', 'disablecopytrace'): False}
+        configoverrides = {('experimental', 'copytrace'): 'on'}
         with repo.ui.configoverride(configoverrides, 'mergecopies'):
             result = orig(repo, cdst, csrc, base)
             if repo.ui.configbool("copytrace", "enableamendcopytrace", True):
diff --git a/tests/copytrace.sh b/tests/copytrace.sh
--- a/tests/copytrace.sh
+++ b/tests/copytrace.sh
@@ -5,6 +5,6 @@
 enablefilldb = True
 fastcopytrace = True
 [experimental]
-disablecopytrace = True
+copytrace = off
 EOF
 }
diff --git a/tests/test-copytrace-amend.t b/tests/test-copytrace-amend.t
--- a/tests/test-copytrace-amend.t
+++ b/tests/test-copytrace-amend.t
@@ -8,7 +8,7 @@
   > [fbamend]
   > userestack=True
   > [experimental]
-  > disablecopytrace=True
+  > copytrace=off
   > evolution=createmarkers
   > EOF
 
diff --git a/tests/test-copytrace-errormsg.t b/tests/test-copytrace-errormsg.t
--- a/tests/test-copytrace-errormsg.t
+++ b/tests/test-copytrace-errormsg.t
@@ -4,7 +4,7 @@
   > rebase=
   > copytrace=$TESTDIR/../hgext3rd/copytrace.py
   > [experimental]
-  > disablecopytrace=True
+  > copytrace=off
   > EOF
 
   $ hg init repo
diff --git a/tests/test-copytrace.t b/tests/test-copytrace.t
--- a/tests/test-copytrace.t
+++ b/tests/test-copytrace.t
@@ -5,7 +5,7 @@
   > rebase=
   > shelve=
   > [experimental]
-  > disablecopytrace=True
+  > copytrace=off
   > EOF
 
 Check filename heuristics (same dirname and same basename)
diff --git a/tests/test-merge-conflictinfo.t b/tests/test-merge-conflictinfo.t
--- a/tests/test-merge-conflictinfo.t
+++ b/tests/test-merge-conflictinfo.t
@@ -363,7 +363,7 @@
      deleted:
   
 
-  $ hg rebase -d 2 -s 1 --config experimental.disablecopytrace=True
+  $ hg rebase -d 2 -s 1 --config experimental.copytrace=off
   rebasing 1:ec87889f5f90 "source"
   other [source] changed file which local [dest] deleted
   use (c)hanged version, leave (d)eleted, or leave (u)nresolved? u
@@ -437,7 +437,7 @@
      deleted:
   
 
-  $ hg rebase -d 2 -s 1 --config experimental.disablecopytrace=True
+  $ hg rebase -d 2 -s 1 --config experimental.copytrace=off
   rebasing 1:e6e7483a8950 "source"
   local [dest] changed file which other [source] deleted
   use (c)hanged version, (d)elete, or leave (u)nresolved? u