diff --git a/src/ert/gui/main_window.py b/src/ert/gui/main_window.py
index b8f4a7d26dd..1bbe1474cf7 100644
--- a/src/ert/gui/main_window.py
+++ b/src/ert/gui/main_window.py
@@ -84,9 +84,7 @@ def __init__(
         self._experiment_panel: Optional[ExperimentPanel] = None
         self._plot_window: Optional[PlotWindow] = None
         self._manage_experiments_panel: Optional[ManageExperimentsPanel] = None
-        self._add_sidebar_button(
-            "Start simulation", QIcon("img:play_circle_outlined.svg")
-        )
+        self._add_sidebar_button("Start simulation", QIcon("img:library_add.svg"))
         self._add_sidebar_button("Create plot", QIcon("img:timeline.svg"))
         self._add_sidebar_button("Manage experiments", QIcon("img:build_wrench.svg"))
         self.results_button = self._add_sidebar_button(
diff --git a/src/ert/gui/resources/gui/img/library_add.svg b/src/ert/gui/resources/gui/img/library_add.svg
new file mode 100644
index 00000000000..cd06455de73
--- /dev/null
+++ b/src/ert/gui/resources/gui/img/library_add.svg
@@ -0,0 +1 @@
+<svg width="24" height="24" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><path fill-rule="evenodd" clip-rule="evenodd" d="M8 2h12c1.1 0 2 .9 2 2v12c0 1.1-.9 2-2 2H8c-1.1 0-2-.9-2-2V4c0-1.1.9-2 2-2M2 6h2v14h14v2H4c-1.1 0-2-.9-2-2zm18 10H8V4h12zm-5-2h-2v-3h-3V9h3V6h2v3h3v2h-3z"/></svg>
diff --git a/src/ert/gui/resources/gui/img/play_circle_outlined.svg b/src/ert/gui/resources/gui/img/play_circle_outlined.svg
deleted file mode 100644
index a2706ec51bb..00000000000
--- a/src/ert/gui/resources/gui/img/play_circle_outlined.svg
+++ /dev/null
@@ -1 +0,0 @@
-<svg width="24" height="24" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><path fill-rule="evenodd" clip-rule="evenodd" d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2m0 18c-4.41 0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8m4-8-6 4.5v-9z"/></svg>