diff --git a/src/api/getSecrets.js b/src/api/getSecrets.js
index 2ea6b11..1288ddf 100644
--- a/src/api/getSecrets.js
+++ b/src/api/getSecrets.js
@@ -1,4 +1,4 @@
-import { DoesNotExistError } from "../types/internalErrors.js";
+import { DoesNotExistError } from "../types/internalErrors";
 import { appendAPIURL, getHeaders } from "./apiUtils.js";
 
 
diff --git a/src/api/getTOTPKeys.js b/src/api/getTOTPKeys.js
index c470866..243ced5 100644
--- a/src/api/getTOTPKeys.js
+++ b/src/api/getTOTPKeys.js
@@ -1,4 +1,4 @@
-import { DoesNotExistError } from "../types/internalErrors.js";
+import { DoesNotExistError } from "../types/internalErrors";
 import { appendAPIURL, getHeaders } from "./apiUtils.js";
 
 
diff --git a/src/api/getTransitKeys.js b/src/api/getTransitKeys.js
index d7454ce..7fd8b92 100644
--- a/src/api/getTransitKeys.js
+++ b/src/api/getTransitKeys.js
@@ -1,4 +1,4 @@
-import { DoesNotExistError } from "../types/internalErrors.js";
+import { DoesNotExistError } from "../types/internalErrors";
 import { appendAPIURL, getHeaders } from "./apiUtils.js";
 
 
diff --git a/src/pages/KeyValue/KeyValueView.js b/src/pages/KeyValue/KeyValueView.js
index a943575..a12933c 100644
--- a/src/pages/KeyValue/KeyValueView.js
+++ b/src/pages/KeyValue/KeyValueView.js
@@ -1,4 +1,4 @@
-import { DoesNotExistError } from "../../types/internalErrors.js";
+import { DoesNotExistError } from "../../types/internalErrors";
 import { Page } from "../../types/Page";
 import { changePage, setErrorText, setTitleElement } from "../../pageUtils";
 import { getSecrets } from "../../api/getSecrets";
diff --git a/src/pages/TOTP/TOTPView.js b/src/pages/TOTP/TOTPView.js
index df43f15..46a6047 100644
--- a/src/pages/TOTP/TOTPView.js
+++ b/src/pages/TOTP/TOTPView.js
@@ -1,5 +1,5 @@
 import { CopyableInputBox } from "../../elements/CopyableInputBox.js";
-import { DoesNotExistError } from "../../types/internalErrors.js";
+import { DoesNotExistError } from "../../types/internalErrors";
 import { Page } from "../../types/Page";
 import { changePage, setErrorText, setPageContent, setTitleElement } from "../../pageUtils";
 import { getTOTPCode } from "../../api/getTOTPCode";
diff --git a/src/pages/Transit/TransitView.js b/src/pages/Transit/TransitView.js
index 4219e8e..a3214d9 100644
--- a/src/pages/Transit/TransitView.js
+++ b/src/pages/Transit/TransitView.js
@@ -1,4 +1,4 @@
-import { DoesNotExistError } from "../../types/internalErrors.js";
+import { DoesNotExistError } from "../../types/internalErrors";
 import { Page } from "../../types/Page";
 import { changePage, setErrorText, setTitleElement } from "../../pageUtils";
 import { getTransitKeys } from "../../api/getTransitKeys";
diff --git a/src/types/internalErrors.js b/src/types/internalErrors.ts
similarity index 53%
rename from src/types/internalErrors.js
rename to src/types/internalErrors.ts
index d4af230..dedf068 100644
--- a/src/types/internalErrors.js
+++ b/src/types/internalErrors.ts
@@ -1,4 +1,4 @@
 // These are all errors that the user won't see
 // but are used internally.
 
-export const DoesNotExistError = new Error("Does not exist.")
\ No newline at end of file
+export const DoesNotExistError: Error = new Error("Does not exist.")
\ No newline at end of file