My guess is that because Dropbox is no longer supported on iOS 9.x you've just been lucky. I'm afraid I dont think its going to be possible to get it to work again. Minimum requirement is iOS12 now.
Today (8-7-2023) I opened zoom on my iPad mini (1st generation) and then a popup came saying that the zoom app version has to be 5.12.2 or higher to sign in. It wouldn't let me join meetings either. I pressed the update button on the popup and it opened the app store, but it showed that it was on the last supported version and no further updates were available. I read through the version history in the app description and it says that zoom version 5.11.3 is the last version to support 32 bit ios devices; and that is the zoom version I have installed which isn't working. How can i get zoom to work on my iPad mini 1st gen?
(It has the last supported ios version which is ios 9.3.5)
For our customers' protection, Apple doesn't disclose, discuss, or confirm security issues until an investigation has occurred and patches or releases are available. Recent releases are listed on the Apple security updates page.
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Apple security documents reference vulnerabilities by CVE-ID when possible.
Released August 25, 2016
Kernel
Available for: iPhone 4s and later, iPad 2 and later, iPod touch (5th generation) and later
Impact: An application may be able to disclose kernel memory
Description: A validation issue was addressed through improved input sanitization.
CVE-2016-4655: Citizen Lab and Lookout
Kernel
Available for: iPhone 4s and later, iPad 2 and later, iPod touch (5th generation) and later
Impact: An application may be able to execute arbitrary code with kernel privileges
Description: A memory corruption issue was addressed through improved memory handling.
CVE-2016-4656: Citizen Lab and Lookout
WebKit
Available for: iPhone 4s and later, iPad 2 and later, iPod touch (5th generation) and later
Impact: Visiting a maliciously crafted website may lead to arbitrary code execution
Description: A memory corruption issue was addressed through improved memory handling.
CVE-2016-4657: Citizen Lab and Lookout
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