MITRE ATT&CK Tabs not showing information after an offline installation

[mhamra]

Wazuh version	Install type	Action performed	Platform
v4.8.0-Beta1	Dashboard	Install	Ubuntu 20.04

During the E2E test https://github.com/wazuh/wazuh/issues/21767, the MITRE ATT&CK Tab pages are not showing correctly.

• Framework Tab
  • The tab shows "There are no results." The documentation shows this page is full of tactics and techniques.
  • After Pressing the refresh button, many pop-up error messages appear.
  • Another pop-up shows that Mitre alerts could not be fetched when opening the pop-up message.
• Dashboard Tab.
  • No dashboard is shown.
• Events Tab.
  • A message "No results match your search criteria" is shown.

[mhamra]

UPDATE

I've found that the root cause of this failure was that the indexer was not working. I've reinstalled the indexer, and I've finished the E2E successfully. The details of the new installation and results are documented in this comment.