I am not sure wheter this was intentional or just to clean the UI. in https://github.com/jenkinsci/jenkins/pull/5851
Before

After
(no little arrow next to build number)

- causes
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JENKINS-68593 Dropdown chevrons overflow in build queue and executor status (regression in 2.340)
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 - Open
 
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JENKINS-68160 Context menu change causes weird behavior in build history (regression in 2.340)
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 - Fixed but Unreleased
 
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JENKINS-68103 Clicking build progress bar no longer jumps to console output (regression in 2.340)
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 - Resolved
 
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JENKINS-68129 Dropdown chevrons no longer separate lists (regression in 2.340)
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 - Closed
 
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JENKINS-68097 Credential domain dropdown floats into text (regression in 2.340)
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 - Closed
 
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JENKINS-68221 Breadcrumbs no longer bold (regression in 2.340)
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 - Closed
 
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