Stable improvements for release

[farmakiG]

Changes in this Pull Request:

• Safe changes of task #1172: All changes of that task without the new: adjust-color-contrast function.

Mandatory checks:

• [X] Branch is up to date (latest changes were fetched from the upstream branch before creating this PR)
• [X] Changes were tested manually
• [ ] Java code changes are unit tested
• [ ] Webtests are successful

To be checked by the reviewer:

• [ ] Clean Java code and unit tested changes
• [X] UI customizablity is preserved: No hard-coded styling and URL references in JSF views

To be checked by the pull request owner:

• [ ] .MASTER/job/BES_MASTER_IT/
• [ ] .MASTER/job/OSCM_WS_Tests_INTERNAL/
• [ ] .MASTER/job/OSCM_WS_Tests_OIDC/
• [ ] .MASTER/job/OSCM_Integration_Tests_INTERNAL/
• [ ] .MASTER/job/OSCM_Integration_Tests_OIDC/

Cross repository and core changes:

• [ ] Interdependent changes have been communicated to the team (if applicable)
• [ ] This pull request includes high risk modifications or core changes (e.g API, datamodel, authentication...). Mandatory reviewers: @goebell or @kowalczyka.

OSCM Build References:

• <CI node number>: <tag>, example: ci10:goebell -est6

Screenshot (if applicable):

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This change is 

[codecov[bot]]

Codecov Report

Merging #1194 (a36c08a) into master (90235a6) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #1194   +/-   ##
=========================================
  Coverage     55.30%   55.30%           
  Complexity    14360    14360           
=========================================
  Files          1371     1371           
  Lines         80347    80347           
  Branches       8585     8585           
=========================================
  Hits          44432    44432           
  Misses        33241    33241           
  Partials       2674     2674