Hi @Margine, David,
I'm glad to hear you solve the problem, if you have any issue about SharePoint, you are welcome to raise a ticket in this forum.
By the way, since the Microsoft Q&A community has a [policy1](https://docs.microsoft.com/en-us/answers/support/accepted-answers) that "The question author cannot accept their own answer. They can only accept answers by others.". and according to the scenario introduced here: [Answering your own questions on Microsoft Q&A 2](https://learn.microsoft.com/en-us/answers/support/self-answering), I would make a brief summary of this thread:
Issue Symptom:
After SharePoint Server 2019 is updated to version KB5002373, the issue of splistreactcontrolsbeforeplt.resx.js file not found when opening list.
Current status:
This is because the language pack associated with KB5002373 is not installed, you can click the link below to download the latest language pack:
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