From 1ed4b39f2663302a02cb81e2736c44b648a30269 Mon Sep 17 00:00:00 2001
From: Guhapriya01 <guhapriyadharmaraj08@gmail.com>
Date: Sun, 16 Aug 2026 14:02:48 +0530
Subject: [PATCH 1/4] fix rangeslider fixed rangemode using placeholder
 counter-axis range

---
 src/components/rangeslider/defaults.js | 4 ++++
 src/plots/cartesian/autorange.js       | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/components/rangeslider/defaults.js b/src/components/rangeslider/defaults.js
index a2efeae718d..3ad94dce797 100644
--- a/src/components/rangeslider/defaults.js
+++ b/src/components/rangeslider/defaults.js
@@ -67,6 +67,10 @@ module.exports = function handleDefaults(layoutIn, layoutOut, axName) {
             var rangeMode = coerceRange('rangemode', rangemodeDflt);
             if(rangeMode !== 'match') {
                 coerceRange('range', yAxOut.range.slice());
+
+                if(rangeMode === 'fixed' && !rangemodeDflt && yAxOut.autorange) {
+                    rangeContainerOut._rangeDfltFromAutorangedAx = true;
+                }
             }
         }
     }
diff --git a/src/plots/cartesian/autorange.js b/src/plots/cartesian/autorange.js
index 9113cd855d4..027228ec5ba 100644
--- a/src/plots/cartesian/autorange.js
+++ b/src/plots/cartesian/autorange.js
@@ -398,7 +398,7 @@ function doAutoRange(gd, ax, presetRange) {
     if(anchorAx && anchorAx.rangeslider) {
         var axeRangeOpts = anchorAx.rangeslider[ax._name];
         if(axeRangeOpts) {
-            if(axeRangeOpts.rangemode === 'auto') {
+            if(axeRangeOpts.rangemode === 'auto' || axeRangeOpts._rangeDfltFromAutorangedAx) {
                 axeRangeOpts.range = getAutoRange(gd, ax);
             }
         }

From db48f745d6398fa553c59bc3d5b8262ddff8b151 Mon Sep 17 00:00:00 2001
From: Guhapriya01 <guhapriyadharmaraj08@gmail.com>
Date: Sun, 16 Aug 2026 14:10:31 +0530
Subject: [PATCH 2/4] add regression test for rangeslider fixed - rangemode fix

---
 test/jasmine/tests/range_slider_test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/jasmine/tests/range_slider_test.js b/test/jasmine/tests/range_slider_test.js
index fed44189d9a..2691e50ebce 100644
--- a/test/jasmine/tests/range_slider_test.js
+++ b/test/jasmine/tests/range_slider_test.js
@@ -1127,6 +1127,30 @@ describe('rangesliders in general', function() {
         .then(done, done.fail);
     });
 
+    it('should not leave "fixed" rangemode on the placeholder range of an autoranged counter axis', function(done) {
+        Plotly.newPlot(gd, [{
+            // use a heatmap because it doesn't add any padding
+            x0: 0, dx: 1,
+            y0: 1, dy: 1,
+            z: [[1, 2, 3], [2, 3, 4], [3, 4, 5]],
+            type: 'heatmap'
+        }], {
+            xaxis: {
+                rangeslider: {visible: true, yaxis: {rangemode: 'fixed'}}
+            }
+        })
+        .then(function() {
+            expect(gd._fullLayout.yaxis.range).toBeCloseToArray([0.5, 3.5], 3);
+            expect(gd._fullLayout.xaxis.rangeslider.yaxis.range).toBeCloseToArray([0.5, 3.5], 3);
+            return Plotly.restyle(gd, {dy: 4});
+        })
+        .then(function() {
+            expect(gd._fullLayout.yaxis.range).toBeCloseToArray([-1, 11], 3);
+            expect(gd._fullLayout.xaxis.rangeslider.yaxis.range).toBeCloseToArray([0.5, 3.5], 3);
+        })
+        .then(done, done.fail);
+    });
+
     it('should be able to turn on rangeslider x/y autorange implicitly by deleting x range', function(done) {
         // this does not apply to y ranges, because the default there is 'match'
         Plotly.newPlot(gd, [{

From 44681ad8c12a2215975bf439904e85f6f3186722 Mon Sep 17 00:00:00 2001
From: Guhapriya01 <guhapriyadharmaraj08@gmail.com>
Date: Sun, 16 Aug 2026 14:34:10 +0530
Subject: [PATCH 3/4] delete _rangeDfltFromAutorangedAx once consumed

---
 src/plots/cartesian/autorange.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/plots/cartesian/autorange.js b/src/plots/cartesian/autorange.js
index 027228ec5ba..870b54d0d5a 100644
--- a/src/plots/cartesian/autorange.js
+++ b/src/plots/cartesian/autorange.js
@@ -400,6 +400,7 @@ function doAutoRange(gd, ax, presetRange) {
         if(axeRangeOpts) {
             if(axeRangeOpts.rangemode === 'auto' || axeRangeOpts._rangeDfltFromAutorangedAx) {
                 axeRangeOpts.range = getAutoRange(gd, ax);
+                delete axeRangeOpts._rangeDfltFromAutorangedAx;
             }
         }
         anchorAx._input.rangeslider[ax._name] = Lib.extendFlat({}, axeRangeOpts);

From 11f79e4f743d48ca94db59466263c67d7616a1b7 Mon Sep 17 00:00:00 2001
From: Guhapriya01 <guhapriyadharmaraj08@gmail.com>
Date: Sun, 16 Aug 2026 14:41:44 +0530
Subject: [PATCH 4/4] add draftlog

---
 draftlogs/7967_fix.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 draftlogs/7967_fix.md

diff --git a/draftlogs/7967_fix.md b/draftlogs/7967_fix.md
new file mode 100644
index 00000000000..a9550d1a6a9
--- /dev/null
+++ b/draftlogs/7967_fix.md
@@ -0,0 +1 @@
+- Fix range slider drawing spurious grey bands on initial render when `rangeslider.yaxis.rangemode` is `"fixed"` and the counter axis is autoranged [[#7967](https://github.com/plotly/plotly.js/pull/7967)]