diff --git a/common/web/input-processor/src/correctionLayout.ts b/common/web/input-processor/src/correctionLayout.ts
index d87f0c9b60..6969d93f40 100644
--- a/common/web/input-processor/src/correctionLayout.ts
+++ b/common/web/input-processor/src/correctionLayout.ts
@@ -81,7 +81,7 @@ export function correctionKeyFilter(key: ActiveKeyBase): boolean {
     return false;
     // Attempt to filter out known non-output keys.
     // Results in a more optimized distribution.
-  } else if(Codes.isKnownOSKModifierKey(key.baseKeyID)) {
+  } else if(Codes.isKeyNotCorrected(key.baseKeyID)) {
     return false;
   } else if(key.isPadding) { // to the user, blank / padding keys do not exist.
     return false;
diff --git a/common/web/input-processor/src/text/inputProcessor.ts b/common/web/input-processor/src/text/inputProcessor.ts
index 74f37ba06c..1b3030f795 100644
--- a/common/web/input-processor/src/text/inputProcessor.ts
+++ b/common/web/input-processor/src/text/inputProcessor.ts
@@ -199,7 +199,7 @@ export default class InputProcessor {
 
     // If it's a key that we 'optimize out' of our fat-finger correction algorithm,
     // we MUST NOT trigger it for this keystroke.
-    let isOnlyLayerSwitchKey = Codes.isKnownOSKModifierKey(keyEvent.kName);
+    let isOnlyLayerSwitchKey = Codes.isKeyNotCorrected(keyEvent.kName);
 
     // Best-guess stopgap for possible custom modifier keys.
     // If a key (1) does not affect the context and (2) shifts the active layer,
diff --git a/common/web/keyboard-processor/src/text/codes.ts b/common/web/keyboard-processor/src/text/codes.ts
index 3f1ebe7afe..654acad68b 100644
--- a/common/web/keyboard-processor/src/text/codes.ts
+++ b/common/web/keyboard-processor/src/text/codes.ts
@@ -86,7 +86,7 @@ const Codes = {
     [')!@#$%^&*(',':+<_>?~', '{|}"']
   ],
 
-  isKnownOSKModifierKey(keyID: string): boolean {
+  isKeyNotCorrected(keyID: string): boolean {
     switch(keyID) {
       case 'K_SHIFT':
       case 'K_LOPT':
@@ -98,13 +98,6 @@ const Codes = {
         if(Codes.keyCodes[keyID] >= 50000) { // A few are used by `sil_euro_latin`.
           return true; // is a 'K_' key defined for layer shifting or 'control' use.
         }
-        // Refer to text/codes.ts - these are Keyman-custom "keycodes" used for
-        // layer shifting keys.  To be safe, we currently let K_TABBACK and
-        // K_TABFWD through, though we might be able to drop them too.
-        const code = Codes[keyID];
-        if(code > 50000 && code < 50011) {
-          return true;
-        }
     }
 
     return false;