RegisterIT#registerExistingUser is flickering

org.openqa.selenium.TimeoutException: 
Expected condition failed: waiting for org.xwiki.test.ui.XWikiWebDriver$$Lambda$1881/0x00007f8590cad380@7f53c6e4
(tried for 10 seconds with 500 milliseconds interval)
Build info: version: '4.40.0', revision: 'b3333f1'
System info: os.name: 'Linux', os.arch: 'amd64', os.version: '6.1.0-37-cloud-amd64', java.version: '17.0.18'
Driver info: org.xwiki.test.ui.XWikiWebDriver
Capabilities {acceptInsecureCerts: false, browserName: chrome, browserVersion: 144.0.7559.96, chrome: {chromedriverVersion: 144.0.7559.96 (d7b80622cfab..., userDataDir: /tmp/org.chromium.Chromium....}, fedcm:accounts: true, goog:chromeOptions: {debuggerAddress: localhost:40629}, goog:loggingPrefs: {browser: ALL}, goog:processID: 175, networkConnectionEnabled: false, pageLoadStrategy: normal, platformName: linux, proxy: Proxy(), se:cdp: ws://172.17.0.8:4444/sessio..., se:cdpVersion: 144.0.7559.96, se:containerName: d26c2c985b5c, se:deleteSessionOnUi: true, se:downloadsEnabled: true, se:gridWebSocketUrl: ws://localhost:15732/sessio..., se:noVncPort: 7900, se:vnc: ws://172.17.0.8:4444/sessio..., se:vncEnabled: true, se:vncLocalAddress: ws://172.17.0.8:7900, setWindowRect: true, strictFileInteractability: false, timeouts: {implicit: 0, pageLoad: 300000, script: 30000}, unhandledPromptBehavior: ignore, webSocketUrl: ws://172.17.0.8:4444/sessio..., webauthn:extension:credBlob: true, webauthn:extension:largeBlob: true, webauthn:extension:minPinLength: true, webauthn:extension:prf: true, webauthn:virtualAuthenticators: true}
Session ID: 85f3651e87e365ecfc1ae716bbdcb408
	at org.openqa.selenium.support.ui.WebDriverWait.timeoutException(WebDriverWait.java:84)
	at org.openqa.selenium.support.ui.FluentWait.until(FluentWait.java:231)
	at org.xwiki.test.ui.XWikiWebDriver.waitUntilCondition(XWikiWebDriver.java:229)
	at org.xwiki.test.ui.XWikiWebDriver.waitUntilElementsAreVisible(XWikiWebDriver.java:331)
	at org.xwiki.test.ui.XWikiWebDriver.waitUntilElementsAreVisible(XWikiWebDriver.java:318)
	at org.xwiki.administration.test.ui.RegisterIT.administrationModalUserCreation(RegisterIT.java:182)
	at org.xwiki.administration.test.ui.RegisterIT.tryToRegister(RegisterIT.java:171)
	at org.xwiki.administration.test.ui.RegisterIT.registerExistingUser(RegisterIT.java:271)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)
	at java.base/java.util.Optional.ifPresent(Optional.java:178)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:992)
	at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)
	at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:992)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
	at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)
	at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
	at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
	at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
	at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
	at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)