#15405 added some pagelets into the application initialisation and updated PageletsHelperTest to retain previous state when testing the Pagelets::Manager class, however it didn't update SmartProxyIntegrationTest which performs very similar modifications and uses Pagelets::Manager.clear.

Running SmartProxyIntegrationTest and HostJSTest in that order will produce test failures, e.g.

SmartProxyIntegrationTest#test_0003_edit page = 11.91 s = .
SmartProxyIntegrationTest#test_0004_show page = 0.22 s = .
SmartProxyIntegrationTest#test_0001_index page = 0.29 s = .
SmartProxyIntegrationTest#test_0002_create new page = 0.36 s = .
SmartProxyIntegrationTest::pagelets on show page#test_0001_show page passes subject into pagelets = 0.38 s = .
HostJSTest::edit page#test_0003_correctly override global params = 2.69 s = .
HostJSTest::edit page#test_0001_class parameters and overrides are displayed correctly for strings = 2.44 s = .
HostJSTest::edit page#test_0002_can override puppetclass lookup values = 0.80 s = .
HostJSTest::create new host page#test_0001_default primary interface is in the overview table = 1.34 s = .
HostJSTest::create new host page#test_0002_choosing a hostgroup overrides other host attributes = 31.37 s = E
HostJSTest::create new host page#test_0004_sets fields to "inherit" when hostgroup is selected = 31.00 s = E
HostJSTest::create new host page#test_0003_saves correct values for inherited fields without hostgroup = 30.89 s = E
HostJSTest::create new host page#test_0005_setting host group updates parameters tab = 1.22 s = .
HostJSTest::hosts index multiple actions#test_0001_show action buttons = 1.27 s = .
HostJSTest::edit page#test_0001_fields are not inherited on edit = 30.92 s = E
HostJSTest::edit page#test_0003_class parameters and overrides are displayed correctly for booleans = 1.62 s = .
HostJSTest::edit page#test_0004_changing host group updates parameters tab = 1.29 s = .
HostJSTest::edit page#test_0002_choosing a hostgroup does not override other host attributes = 31.43 s = E
HostJSTest::NIC modal window::editing interfaces#test_0002_ok button updates overview table = 1.54 s = .
HostJSTest::NIC modal window::editing interfaces#test_0001_click on edit opens modal = 1.45 s = .
HostJSTest::NIC modal window::adding interfaces#test_0001_click on add opens modal = 1.48 s = .
HostJSTest::NIC modal window::adding interfaces#test_0003_setting primary updates host name = 32.24 s = .
HostJSTest::NIC modal window::adding interfaces#test_0004_selecting domain updates subnet list = 31.75 s = .
HostJSTest::NIC modal window::adding interfaces#test_0002_ok button adds new interface = 1.55 s = .
HostJSTest::NIC modal window::adding interfaces#test_0005_selecting domain updates puppetclass parameters = 2.00 s = .
HostJSTest::NIC modal window::adding interfaces#test_0006_selecting type updates interface fields = 1.53 s = .
HostJSTest::NIC modal window::switching flags from the overview table#test_0001_switch primary = 1.89 s = .
HostJSTest::NIC modal window::switching flags from the overview table#test_0002_switch provisioning = 1.91 s = .
HostJSTest::NIC modal window::removing interfaces#test_0001_remove interface = 1.96 s = .
HostJSTest::Puppet Classes tab::has inherited Puppetclasses#test_0001_it mentions the hostgroup by name in the tooltip = 31.01 s = E
HostJSTest::Puppet Classes tab::has inherited Puppetclasses#test_0002_it shows a header mentioning the hostgroup inherited from = 31.18 s = E

Finished in 757.815452s, 0.0409 runs/s, 0.1478 assertions/s.

  1) Error:
HostJSTest::create new host page#test_0002_choosing a hostgroup overrides other host attributes:
Capybara::ElementNotFound: Unable to find css "#host_environment_id + .input-group-btn .btn" 
    test/integration/shared/host_finders.rb:42:in `click_on_inherit'
    test/integration/host_js_test.rb:135:in `block (2 levels) in <class:HostJSTest>'

  2) Error:
HostJSTest::create new host page#test_0004_sets fields to "inherit" when hostgroup is selected:
Capybara::ElementNotFound: Unable to find css "#s2id_host_environment_id" 
    test/integration_test_helper.rb:87:in `select2'
    test/integration/host_js_test.rb:190:in `block (2 levels) in <class:HostJSTest>'

[..]

  7) Error:
HostJSTest::Puppet Classes tab::has inherited Puppetclasses#test_0002_it shows a header mentioning the hostgroup inherited from:
Capybara::ElementNotFound: Unable to find link "Puppet Classes" with href "#puppet_klasses" 
    test/integration/host_js_test.rb:549:in `block (3 levels) in <class:HostJSTest>'