diff --git a/javascript/extraNetworks.js b/javascript/extraNetworks.js
index 7015a6a2a..4b6559822 100644
--- a/javascript/extraNetworks.js
+++ b/javascript/extraNetworks.js
@@ -1,3 +1,10 @@
+// Prevent eslint errors on functions defined in other files.
+/*global
+    ExtraNetworksClusterizeTreeList,
+    ExtraNetworksClusterizeCardsList,
+*/
+/*eslint no-undef: "error"*/
+
 const SEARCH_INPUT_DEBOUNCE_TIME_MS = 250;
 
 const re_extranet = /<([^:^>]+:[^:]+):[\d.]+>(.*)/;
@@ -23,7 +30,7 @@ const isStringLogError = x => {
     console.error("expected string, got:", typeof x);
     return false;
 };
-const isNull = x => typeof x === "null" || x === null;
+const isNull = x => x === null;
 const isUndefined = x => typeof x === "undefined" || x === undefined;
 // checks both null and undefined for simplicity sake.
 const isNullOrUndefined = x => isNull(x) || isUndefined(x);
diff --git a/javascript/extraNetworksClusterizeList.js b/javascript/extraNetworksClusterizeList.js
index 9cc6f372e..2a2846055 100644
--- a/javascript/extraNetworksClusterizeList.js
+++ b/javascript/extraNetworksClusterizeList.js
@@ -1,3 +1,20 @@
+// Prevent eslint errors on functions defined in other files.
+/*global
+    isString,
+    isStringLogError,
+    isNull,
+    isUndefined,
+    isNullOrUndefined,
+    isNullOrUndefinedLogError,
+    isElement,
+    isElementLogError,
+    getElementByIdLogError,
+    querySelectorLogError,
+    waitForElement,
+    Clusterize
+*/
+/*eslint no-undef: "error"*/
+
 const JSON_UPDATE_DEBOUNCE_TIME_MS = 250;
 const RESIZE_DEBOUNCE_TIME_MS = 250;
 // Collators used for sorting.
@@ -89,15 +106,6 @@ const htmlStringToElement = function(str) {
     return tmp.body.firstElementChild;
 };
 
-const getComputedValue = function(container, css_property) {
-    /** Gets a property value for the computed style of an element. */
-    return parseInt(
-        window.getComputedStyle(container, null)
-            .getPropertyValue(css_property)
-            .split("px")[0]
-    );
-};
-
 const calcColsPerRow = function(parent, child) {
     /** Calculates the number of columns of children that can fit in a parent's visible width. */
     const parent_inner_width = parent.offsetWidth - getComputedPaddingDims(parent).width;