Package libicu76 is not installed.

[Steven Sostrom]

This is an old problem, but sparksdr (2.0.995) will not install on Ubuntu 26.04 LTS.

dpkg: dependency problems prevent configuration of sparksdr:
 sparksdr depends on libicu76 | libicu75 | libicu74 | libicu73 | libicu72 | libicu71 | libicu70 | libicu69 | libicu68 | libicu67 | libicu66 | libicu65 | libicu64 | libicu63 | libicu62 | libicu61 | libicu60 | libicu59 | libicu58 | libicu57 | libicu56 | libicu55 | libicu54 | libicu53 | libicu52; however:
  Package libicu76 is not installed.
-on-and-on.

The current Ubuntu package is 

libicu78/resolute,now 78.2-2ubuntu1 arm64

They are only a few versions ahead and climbing...