--- calamares-3.2.15/src/modules/partition/core/PartitionLayout.cpp.orig	2019-10-12 12:00:31.660000000 +0200
+++ calamares-3.2.15/src/modules/partition/core/PartitionLayout.cpp	2019-10-12 12:01:10.894000000 +0200
@@ -179,6 +179,12 @@
         else
             minSize = 0;
 
+        if ( availableSize < 5 * 1024 * 1024) {
+            cWarning() << "Partition" << part.partMountPoint << "available size"
+                << "is insufficient to add partition, skipping...";
+            continue;
+        }
+
         if ( part.partMaxSize.isValid() )
             maxSize = part.partMaxSize.toSectors( totalSize, dev->logicalSize() );
         else