TYPO3 Core

Good catch. Issue #91786 change the loading of RequireJS modules, basically to avoid inline JavaScript code.
However, the previous implementation in PageRenderer::loadRequireJsModule maintained a "duplicate check" for each module and its callback function.

// ...
$inlineCodeKey = $mainModuleName . sha1($callBackFunction);
// ...
$this->addJsInlineCode('RequireJS-Module-' . $inlineCodeKey, $javaScriptCode);

This initialization (of different instance) can be the intended behavior, the new way has to be a bit more explicit, e.g.

$instruction = JavaScriptModuleInstruction::create('TYPO3/CMS/Redirects/EventHandler.js')
  ->addFlags(JavaScriptModuleInstruction::FLAG_USE_TOP_WINDOW)
  ->invoke('dispatchCustomEvent', 'typo3:redirects:slugChanged', $params['parameter']);

if (!$javaScriptRenderer->hasJavaScriptModuleInstruction($instruction, CONSIDER_ALL)) {
  $javaScriptRenderer->addJavaScriptModuleInstruction(instruction);
}

// where the flags could be among
// CONSIDER_NAME: just checking the module name
// CONSIDER_FLAGS: just checking internal flags
// CONSIDER_INSTANTIATION: ... instance args ... 
// CONSIDER_INVOCATION: ... invokes ...
// CONSIDER_ASSIGNMENTS: ... assignments ...
// CONSIDER_ALL: all of the above

Patch set 1 for branch main of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at https://review.typo3.org/c/Packages/TYPO3.CMS/+/73178