diff --git a/tests/system/suite_debugger/envvars b/tests/system/suite_debugger/envvars
new file mode 100644
index 0000000000000000000000000000000000000000..00aad3eab7dde282f5e8f2597f489cd170b51e37
--- /dev/null
+++ b/tests/system/suite_debugger/envvars
@@ -0,0 +1 @@
+QT_PLATFORM_PLUGIN=nonesuch
diff --git a/tests/system/suite_editors/envvars b/tests/system/suite_editors/envvars
new file mode 100644
index 0000000000000000000000000000000000000000..00aad3eab7dde282f5e8f2597f489cd170b51e37
--- /dev/null
+++ b/tests/system/suite_editors/envvars
@@ -0,0 +1 @@
+QT_PLATFORM_PLUGIN=nonesuch