Resolves: tdf#152411 clear before freeze to let gtk a11y drop reference

Change-Id: I2c0f852a0432e7319644b0ea11533b6d153b4ac7
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/143780
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/starmath/source/ElementsDockingWindow.cxx b/starmath/source/ElementsDockingWindow.cxx
index 16a22d2..1ea324d 100644
--- a/starmath/source/ElementsDockingWindow.cxx
+++ b/starmath/source/ElementsDockingWindow.cxx
@@ -574,8 +574,8 @@ void SmElementsControl::setElementSetIndex(int nSetIndex)

void SmElementsControl::addElements(int nCategory)
{
    mpIconView->clear(); // tdf#152411 clear before freeze to let gtk a11y drop reference
    mpIconView->freeze();
    mpIconView->clear();
    mpIconView->set_item_width(0);
    maItemDatas.clear();