diff --git a/ivette/src/dome/renderer/graph/diagram.tsx b/ivette/src/dome/renderer/graph/diagram.tsx
index d594f647ca21f1aa19bdea0b29be528c7f48262b..5764a97e7313d3a15cc929d6405e1d16c253f900 100644
--- a/ivette/src/dome/renderer/graph/diagram.tsx
+++ b/ivette/src/dome/renderer/graph/diagram.tsx
@@ -349,7 +349,7 @@ class Builder {
   // --- Edge
   edge(e: Edge): void {
     const { line = 'solid', head = 'arrow', tail = 'none' } = e;
-    const tooltip = e.title ?? e.label ?? `${e.source} -> ${e.target}`;
+    const tooltip = e.title ?? e.label;
     if (e.aligned === true)
       this
         .print('{ rank=same; ')
diff --git a/ivette/src/frama-c/plugins/region/memory.tsx b/ivette/src/frama-c/plugins/region/memory.tsx
index 42e4ac7f8de6f78166ab7d811ca027408e149c09..e04a8e56bf3380f062b9c63dd04b982b406fd7e4 100644
--- a/ivette/src/frama-c/plugins/region/memory.tsx
+++ b/ivette/src/frama-c/plugins/region/memory.tsx
@@ -54,7 +54,7 @@ function makeRecord(
     cells.push({ label, port });
   });
   if (offset !== sizeof)
-    cells.push(`#${sizeof-offset}b`);
+    cells.push(`#${sizeof - offset}b`);
   return cells;
 }
 
@@ -70,11 +70,12 @@ function makeDiagram(regions: readonly Region.region[]): Diagram {
     const id = `n${r.node}`;
     // --- Color
     const color =
-      !r.typed ? 'red' :
-        r.pointed !== undefined
-          ? (r.writes ? 'orange' : 'yellow')
-          : (r.writes && r.reads) ? 'green' :
-            r.writes ? 'pink' : r.reads ? 'grey' : 'white';
+      (!r.writes && !r.reads) ? undefined :
+        !r.typed ? 'red' :
+          r.pointed !== undefined
+            ? (r.writes ? 'orange' : 'yellow')
+            : (r.writes && r.reads) ? 'green' :
+              r.writes ? 'pink' : 'grey';
     // --- Shape
     const font = r.ranges.length > 0 ? 'mono' : 'sans';
     const cells = makeRecord(edges, id, r.sizeof, r.ranges);
diff --git a/src/plugins/region/tests/region/comp.c b/src/plugins/region/tests/region/comp.i
similarity index 100%
rename from src/plugins/region/tests/region/comp.c
rename to src/plugins/region/tests/region/comp.i