Sometimes you can get into what seems like a very serious problem when you update an application that results in the tool being completely broken. This can happen even if the update was suggested and validated by the software manager of your distribution.
For example, the manager notifies you of a few application updates and you simply hit "ok" to apply them; the process applies all the dependencies and goes complete successfully, yet one of the updated apps doesn't start, or else crashes as it launches with an undecipherable error. In such cases, you are unlikely to find a direct solution on the web, since the error is likely caused by a code update that is but a few hours old. The Stack Overflow volunteers aren't that quick at providing new answers 😉
You can't mitigate a critical program error, you can't undo an installation, and you probably don't have the time or resources to waste figuring out what went wrong and how to fix it (assuming that is even possible). You will need to go back and re-instate a working version of the now faulty application. Luckily, all Linux application providers maintain a repository of their older versions. This means that you will be able to find a slightly older package that either matches the one you just updated or else one that will work properly on your system. That is one of the reasons why most package filenames append the version number: it makes it easier for humans to navigate the packages and their dependencies in case there's trouble.
Here's how you can revert a package when a critical error occurs after an update:
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