diff --git a/README.md b/README.md
index 4f08254..0acc86a 100644
--- a/README.md
+++ b/README.md
@@ -61,12 +61,12 @@ Examples on using table-sort-js with frontend frameworks such as [React.js](http
 
 <br>
 
-| &lt;th&gt; classes | Description                                                                                                                              |
-| ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------- |
-| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g &lt;td data-sort="42"&gt;. Useful for doing custom sorts.  |
-| "dates-mdy-sort"   | Sorts dates in US style mm/dd/yyyy format;. e.g (12/28/2023). Can use "/" or "-" as separator. Overides inferred "dates-dmy-sort" class. |
-| "onload-sort"      | Sort column on loading of the page. Simulates a click from the user. (can only sort onload for one column)                               |
-| "disable-sort"     | Disallow sorting the table by this specific column.                                                                                      |
+| &lt;th&gt; classes | Description                                                                                                                                                             |
+| ------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g &lt;td data-sort="42"&gt;. Useful for doing custom sorts. |
+| "dates-mdy-sort"   | Sorts dates in US style mm/dd/yyyy format;. e.g (12/28/2023). Can use "/" or "-" as separator. Overides inferred "dates-dmy-sort" class.                                |
+| "onload-sort"      | Sort column on loading of the page. Simulates a click from the user. (can only sort onload for one column)                                                              |
+| "disable-sort"     | Disallow sorting the table by this specific column.                                                                                                                     |
 
 <br>
 
diff --git a/browser-extensions/chrome/manifest.json b/browser-extensions/chrome/manifest.json
index 2268f05..49e8ee5 100644
--- a/browser-extensions/chrome/manifest.json
+++ b/browser-extensions/chrome/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version": 3,
   "author": "Lee Wannacott",
   "name": "table-sort-js",
-  "version": "1.18.0",
+  "version": "1.18.1",
   "description": "Makes tables sortable using table-sort-js: https://github.com/LeeWannacott/table-sort-js",
   "icons": { "48": "icons/t.png" },
   "browser_action": {
diff --git a/browser-extensions/chrome/table-sort-js.zip b/browser-extensions/chrome/table-sort-js.zip
index 435b1f8..c04a81d 100644
Binary files a/browser-extensions/chrome/table-sort-js.zip and b/browser-extensions/chrome/table-sort-js.zip differ
diff --git a/browser-extensions/chrome/table-sort.js b/browser-extensions/chrome/table-sort.js
index 455c4d2..1a9a2c0 100644
--- a/browser-extensions/chrome/table-sort.js
+++ b/browser-extensions/chrome/table-sort.js
@@ -55,57 +55,61 @@ function tableSortJs(testingTableSortJS = false, domDocumentWindow = document) {
   }
 
   function inferSortClasses(tableRows, columnIndex, column, th) {
-    const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
-    const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
-    // Don't infer dates with delimiter "."; as could capture semantic version numbers.
-    const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
-    const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
-    // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
-    const numericRegex =
-      /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
-    const inferableClasses = {
-      runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
-      filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
-      dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
-      ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
-      numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
-    };
-    let classNameAdded = false;
-    let regexNotFoundCount = 0;
-    const threshold = Math.ceil(tableRows.length / 2);
-    for (let tr of tableRows) {
-      if (regexNotFoundCount >= threshold) {
-        break;
-      }
-      const tableColumn = tr
-        .querySelectorAll("td")
-        .item(
-          column.span[columnIndex] === 1
-            ? column.spanSum[columnIndex] - 1
-            : column.spanSum[columnIndex] - column.span[columnIndex]
-        );
-      let foundMatch = false;
-      for (let key of Object.keys(inferableClasses)) {
-        let classRegexp = inferableClasses[key].regexp;
-        if (tableColumn?.innerText !== undefined) {
-          if (tableColumn.innerText.match(classRegexp)) {
-            foundMatch = true;
-            inferableClasses[key].count++;
+    try {
+      const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
+      const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
+      // Don't infer dates with delimiter "."; as could capture semantic version numbers.
+      const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
+      const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
+      // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
+      const numericRegex =
+        /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
+      const inferableClasses = {
+        runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
+        filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
+        dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
+        ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
+        numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
+      };
+      let classNameAdded = false;
+      let regexNotFoundCount = 0;
+      const threshold = Math.ceil(tableRows.length / 2);
+      for (let tr of tableRows) {
+        if (regexNotFoundCount >= threshold) {
+          break;
+        }
+        const tableColumn = tr
+          .querySelectorAll("td")
+          .item(
+            column.span[columnIndex] === 1
+              ? column.spanSum[columnIndex] - 1
+              : column.spanSum[columnIndex] - column.span[columnIndex]
+          );
+        let foundMatch = false;
+        for (let key of Object.keys(inferableClasses)) {
+          let classRegexp = inferableClasses[key].regexp;
+          if (tableColumn.innerText !== undefined) {
+            if (tableColumn.innerText.match(classRegexp)) {
+              foundMatch = true;
+              inferableClasses[key].count++;
+            }
+          }
+          if (inferableClasses[key].count >= threshold) {
+            th.classList.add(inferableClasses[key].class);
+            classNameAdded = true;
+            break;
           }
         }
-        if (inferableClasses[key].count >= threshold) {
-          th.classList.add(inferableClasses[key].class);
-          classNameAdded = true;
+        if (classNameAdded) {
           break;
         }
+        if (!foundMatch) {
+          regexNotFoundCount++;
+          continue;
+        }
       }
-      if (classNameAdded) {
-        break;
-      }
-      if (!foundMatch) {
-        regexNotFoundCount++;
-        continue;
-      }
+    } catch (e) {
+      console.log(e);
     }
   }
 
diff --git a/browser-extensions/firefox/manifest.json b/browser-extensions/firefox/manifest.json
index 354896d..e9af1a3 100644
--- a/browser-extensions/firefox/manifest.json
+++ b/browser-extensions/firefox/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version": 2,
   "author": "Lee Wannacott",
   "name": "table-sort-js",
-  "version": "1.18.0",
+  "version": "1.18.1",
   "description": "Makes tables sortable using table-sort-js: https://github.com/LeeWannacott/table-sort-js",
   "icons": { "48": "icons/t.png" },
   "browser_action": {
diff --git a/browser-extensions/firefox/table-sort-js.zip b/browser-extensions/firefox/table-sort-js.zip
index 5a70363..efd4576 100644
Binary files a/browser-extensions/firefox/table-sort-js.zip and b/browser-extensions/firefox/table-sort-js.zip differ
diff --git a/browser-extensions/firefox/table-sort.js b/browser-extensions/firefox/table-sort.js
index 455c4d2..1a9a2c0 100644
--- a/browser-extensions/firefox/table-sort.js
+++ b/browser-extensions/firefox/table-sort.js
@@ -55,57 +55,61 @@ function tableSortJs(testingTableSortJS = false, domDocumentWindow = document) {
   }
 
   function inferSortClasses(tableRows, columnIndex, column, th) {
-    const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
-    const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
-    // Don't infer dates with delimiter "."; as could capture semantic version numbers.
-    const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
-    const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
-    // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
-    const numericRegex =
-      /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
-    const inferableClasses = {
-      runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
-      filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
-      dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
-      ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
-      numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
-    };
-    let classNameAdded = false;
-    let regexNotFoundCount = 0;
-    const threshold = Math.ceil(tableRows.length / 2);
-    for (let tr of tableRows) {
-      if (regexNotFoundCount >= threshold) {
-        break;
-      }
-      const tableColumn = tr
-        .querySelectorAll("td")
-        .item(
-          column.span[columnIndex] === 1
-            ? column.spanSum[columnIndex] - 1
-            : column.spanSum[columnIndex] - column.span[columnIndex]
-        );
-      let foundMatch = false;
-      for (let key of Object.keys(inferableClasses)) {
-        let classRegexp = inferableClasses[key].regexp;
-        if (tableColumn?.innerText !== undefined) {
-          if (tableColumn.innerText.match(classRegexp)) {
-            foundMatch = true;
-            inferableClasses[key].count++;
+    try {
+      const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
+      const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
+      // Don't infer dates with delimiter "."; as could capture semantic version numbers.
+      const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
+      const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
+      // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
+      const numericRegex =
+        /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
+      const inferableClasses = {
+        runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
+        filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
+        dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
+        ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
+        numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
+      };
+      let classNameAdded = false;
+      let regexNotFoundCount = 0;
+      const threshold = Math.ceil(tableRows.length / 2);
+      for (let tr of tableRows) {
+        if (regexNotFoundCount >= threshold) {
+          break;
+        }
+        const tableColumn = tr
+          .querySelectorAll("td")
+          .item(
+            column.span[columnIndex] === 1
+              ? column.spanSum[columnIndex] - 1
+              : column.spanSum[columnIndex] - column.span[columnIndex]
+          );
+        let foundMatch = false;
+        for (let key of Object.keys(inferableClasses)) {
+          let classRegexp = inferableClasses[key].regexp;
+          if (tableColumn.innerText !== undefined) {
+            if (tableColumn.innerText.match(classRegexp)) {
+              foundMatch = true;
+              inferableClasses[key].count++;
+            }
+          }
+          if (inferableClasses[key].count >= threshold) {
+            th.classList.add(inferableClasses[key].class);
+            classNameAdded = true;
+            break;
           }
         }
-        if (inferableClasses[key].count >= threshold) {
-          th.classList.add(inferableClasses[key].class);
-          classNameAdded = true;
+        if (classNameAdded) {
           break;
         }
+        if (!foundMatch) {
+          regexNotFoundCount++;
+          continue;
+        }
       }
-      if (classNameAdded) {
-        break;
-      }
-      if (!foundMatch) {
-        regexNotFoundCount++;
-        continue;
-      }
+    } catch (e) {
+      console.log(e);
     }
   }
 
diff --git a/npm/README.md b/npm/README.md
index 37ca0b9..0acc86a 100644
--- a/npm/README.md
+++ b/npm/README.md
@@ -61,12 +61,12 @@ Examples on using table-sort-js with frontend frameworks such as [React.js](http
 
 <br>
 
-| &lt;th&gt; classes | Description                                                                                                                              |
-| ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------- |
-| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g &lt;td data-sort="42"&gt;  |
-| "dates-mdy-sort"   | Sorts dates in US style mm/dd/yyyy format;. e.g (12/28/2023). Can use "/" or "-" as separator. Overides inferred "dates-dmy-sort" class. |
-| "onload-sort"      | Sort column on loading of the page. Simulates a click from the user. (can only sort onload for one column)                               |
-| "disable-sort"     | Disallow sorting the table by this specific column.                                                                                      |
+| &lt;th&gt; classes | Description                                                                                                                                                             |
+| ------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g &lt;td data-sort="42"&gt;. Useful for doing custom sorts. |
+| "dates-mdy-sort"   | Sorts dates in US style mm/dd/yyyy format;. e.g (12/28/2023). Can use "/" or "-" as separator. Overides inferred "dates-dmy-sort" class.                                |
+| "onload-sort"      | Sort column on loading of the page. Simulates a click from the user. (can only sort onload for one column)                                                              |
+| "disable-sort"     | Disallow sorting the table by this specific column.                                                                                                                     |
 
 <br>
 
diff --git a/npm/package.json b/npm/package.json
index 880a314..0a910a8 100644
--- a/npm/package.json
+++ b/npm/package.json
@@ -1,6 +1,6 @@
 {
   "name": "table-sort-js",
-  "version": "1.18.0",
+  "version": "1.18.1",
   "description": "A JavaScript client-side HTML table sorting library with no dependencies required.",
   "license": "MIT",
   "repository": "LeeWannacott/table-sort-js",
diff --git a/npm/table-sort.js b/npm/table-sort.js
index 455c4d2..1a9a2c0 100644
--- a/npm/table-sort.js
+++ b/npm/table-sort.js
@@ -55,57 +55,61 @@ function tableSortJs(testingTableSortJS = false, domDocumentWindow = document) {
   }
 
   function inferSortClasses(tableRows, columnIndex, column, th) {
-    const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
-    const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
-    // Don't infer dates with delimiter "."; as could capture semantic version numbers.
-    const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
-    const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
-    // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
-    const numericRegex =
-      /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
-    const inferableClasses = {
-      runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
-      filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
-      dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
-      ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
-      numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
-    };
-    let classNameAdded = false;
-    let regexNotFoundCount = 0;
-    const threshold = Math.ceil(tableRows.length / 2);
-    for (let tr of tableRows) {
-      if (regexNotFoundCount >= threshold) {
-        break;
-      }
-      const tableColumn = tr
-        .querySelectorAll("td")
-        .item(
-          column.span[columnIndex] === 1
-            ? column.spanSum[columnIndex] - 1
-            : column.spanSum[columnIndex] - column.span[columnIndex]
-        );
-      let foundMatch = false;
-      for (let key of Object.keys(inferableClasses)) {
-        let classRegexp = inferableClasses[key].regexp;
-        if (tableColumn?.innerText !== undefined) {
-          if (tableColumn.innerText.match(classRegexp)) {
-            foundMatch = true;
-            inferableClasses[key].count++;
+    try {
+      const runtimeRegex = /^(\d+h)?\s?(\d+m)?\s?(\d+s)?$/i;
+      const fileSizeRegex = /^([.0-9]+)\s?(B|KB|KiB|MB|MiB|GB|GiB|TB|TiB)/i;
+      // Don't infer dates with delimiter "."; as could capture semantic version numbers.
+      const dmyRegex = /^(\d\d?)[/-](\d\d?)[/-]((\d\d)?\d\d)/;
+      const ymdRegex = /^(\d\d\d\d)[/-](\d\d?)[/-](\d\d?)/;
+      // const numericRegex = /^(?:\(\d+(?:\.\d+)?\)|-?\d+(?:\.\d+)?)$/;  doesn't handle commas
+      const numericRegex =
+        /^-?(?:\d{1,3}(?:[',]\d{3})*(?:\.\d+)?|\d+(?:\.\d+)?(?:[',]\d{3})*?)$/;
+      const inferableClasses = {
+        runtime: { regexp: runtimeRegex, class: "runtime-sort", count: 0 },
+        filesize: { regexp: fileSizeRegex, class: "file-size-sort", count: 0 },
+        dmyDates: { regexp: dmyRegex, class: "dates-dmy-sort", count: 0 },
+        ymdDates: { regexp: ymdRegex, class: "dates-ymd-sort", count: 0 },
+        numericRegex: { regexp: numericRegex, class: "numeric-sort", count: 0 },
+      };
+      let classNameAdded = false;
+      let regexNotFoundCount = 0;
+      const threshold = Math.ceil(tableRows.length / 2);
+      for (let tr of tableRows) {
+        if (regexNotFoundCount >= threshold) {
+          break;
+        }
+        const tableColumn = tr
+          .querySelectorAll("td")
+          .item(
+            column.span[columnIndex] === 1
+              ? column.spanSum[columnIndex] - 1
+              : column.spanSum[columnIndex] - column.span[columnIndex]
+          );
+        let foundMatch = false;
+        for (let key of Object.keys(inferableClasses)) {
+          let classRegexp = inferableClasses[key].regexp;
+          if (tableColumn.innerText !== undefined) {
+            if (tableColumn.innerText.match(classRegexp)) {
+              foundMatch = true;
+              inferableClasses[key].count++;
+            }
+          }
+          if (inferableClasses[key].count >= threshold) {
+            th.classList.add(inferableClasses[key].class);
+            classNameAdded = true;
+            break;
           }
         }
-        if (inferableClasses[key].count >= threshold) {
-          th.classList.add(inferableClasses[key].class);
-          classNameAdded = true;
+        if (classNameAdded) {
           break;
         }
+        if (!foundMatch) {
+          regexNotFoundCount++;
+          continue;
+        }
       }
-      if (classNameAdded) {
-        break;
-      }
-      if (!foundMatch) {
-        regexNotFoundCount++;
-        continue;
-      }
+    } catch (e) {
+      console.log(e);
     }
   }