diff --git a/src/ol/has.js b/src/ol/has.js
index 36ea64dc48..91fe1c07b0 100644
--- a/src/ol/has.js
+++ b/src/ol/has.js
@@ -133,7 +133,9 @@ ol.has.WEBGL;
               (gl.getParameter(gl.MAX_TEXTURE_SIZE));
           extensions = gl.getSupportedExtensions();
         }
-      } catch (e) {}
+      } catch (e) {
+        // pass
+      }
     }
     ol.has.WEBGL = hasWebGL;
     ol.WEBGL_EXTENSIONS = extensions;
diff --git a/src/ol/pointer/pointerevent.js b/src/ol/pointer/pointerevent.js
index 1905250ea0..dadec5e802 100644
--- a/src/ol/pointer/pointerevent.js
+++ b/src/ol/pointer/pointerevent.js
@@ -272,5 +272,6 @@ ol.pointer.PointerEvent.HAS_BUTTONS = false;
     var ev = new MouseEvent('click', {buttons: 1});
     ol.pointer.PointerEvent.HAS_BUTTONS = ev.buttons === 1;
   } catch (e) {
+    // pass
   }
 })();
diff --git a/src/ol/webgl/webgl.js b/src/ol/webgl/webgl.js
index 2ed574eea0..cd74b587e0 100644
--- a/src/ol/webgl/webgl.js
+++ b/src/ol/webgl/webgl.js
@@ -38,6 +38,7 @@ ol.webgl.getContext = function(canvas, opt_attributes) {
         return /** @type {!WebGLRenderingContext} */ (context);
       }
     } catch (e) {
+      // pass
     }
   }
   return null;