Local Queue
Local Queue keeps a list of changes that follow from an entry you are making in Client.
If you are creating an invoice this may need to update inventory and accounting, asap. To keep your data perfect, this is handled as a transaction, which saves all or nothing.
If you cancel, or if you computer crashes, nothing is saved and your data is unchanged. If you save, you need to allow a minute for updates to upload to be able to quit Client.
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