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Area

core

Describe the bug

When running in development mode (start-dev), the static theme resources (css, js, images) have a Cache-Control header with a value of max-age=2592000 instead of no-cache.

Until version 26.4.4 the static resources had a cache-control header of no-cache. Beginning with 26.4.5 (and also nightly) the cache-control header is set to the default production mode value.

Version

26.4.5, nightly

Regression

[x] The issue is a regression

Expected behavior

When starting Keycloak in development mode, the Cache-Control header of all static theme resources should be no-cache, like before.

Actual behavior

When starting Keycloak in development mode, the Cache-Control header of all static theme resources is max-age=2592000 (default for production mode)

How to Reproduce?

Start a Keycloak server (26.4.5 or nightly) with start-dev command and inspect the headers of the static theme resources.

Anything else?

No response