Marketplace client fails to connect behind proxy

Let's make sure issue is not already fixed in latest builds first.

- [x] I verified I can reproduce this issue against [latest Integration Build of Eclipse SDK](https://download.eclipse.org/eclipse/downloads/)

This seems potentially related to #1690

## Steps to reproduce

From a fresh installation and clean workspace:
While using a company proxy or other security appliance which inspects TLS traffic, go to *Help > Eclipse Marketplace...* and observe that the following error is displayed:
```
Cannot open Eclipse Marketplace
Cannot install remote marketplace locations: Cannot complete request to
https://marketplace.eclipse.org/catalogs/api/p: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
```

## Workaround

Setting `-Djavax.net.ssl.trustStoreType=Windows-ROOT` and `-Djavax.net.ssl.trustStore=NONE` resolves the issue. However, I was under the impression that `-Declipse.platform.mergeTrust=true` was supposed to make this kind of trust store manipulation unnecessary. It seems the marketplace client is not using the merged trust, or something else is wrong.

## Here is some relevant log output

From `/.metadata/.log`
```
!ENTRY org.eclipse.epp.mpc.ui 4 0 2026-03-19 11:15:34.052
!MESSAGE Cannot open Eclipse Marketplace
!STACK 1
org.eclipse.core.runtime.CoreException: Cannot install remote marketplace locations: Cannot complete request to https://marketplace.eclipse.org/catalogs/api/p: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.createConfiguration(AbstractMarketplaceWizardCommand.java:105)
at org.eclipse.epp.internal.mpc.ui.commands.MarketplaceWizardCommand.createConfiguration(MarketplaceWizardCommand.java:64)
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.execute(AbstractMarketplaceWizardCommand.java:67)
at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:277)
at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:98)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:58)
at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:305)
at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:237)
at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:174)
at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:165)
at org.eclipse.core.commands.Command.executeWithChecks(Command.java:488)
at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:484)
at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:204)
at org.eclipse.e4.ui.workbench.renderers.swt.HandledContributionItem.executeItem(HandledContributionItem.java:446)
at org.eclipse.e4.ui.workbench.renderers.swt.AbstractContributionItem.handleWidgetSelection(AbstractContributionItem.java:471)
at org.eclipse.e4.ui.workbench.renderers.swt.AbstractContributionItem.lambda$2(AbstractContributionItem.java:493)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:91)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4349)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1217)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4147)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3735)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1160)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1051)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:684)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:583)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:173)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:185)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:219)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:149)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:115)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:467)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:298)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:615)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:563)
at org.eclipse.equinox.launcher.Main.run(Main.java:1415)
Caused by: org.eclipse.core.runtime.CoreException: Cannot complete request to https://marketplace.eclipse.org/catalogs/api/p: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:193)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:128)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:115)
at org.eclipse.epp.internal.mpc.core.service.DefaultCatalogService.listCatalogs(DefaultCatalogService.java:49)
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.lambda$0(AbstractMarketplaceWizardCommand.java:169)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:123)
Caused by: org.eclipse.core.runtime.CoreException: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:188)
... 5 more
Caused by: java.io.IOException: Pipe closed
at java.base/java.io.PipedInputStream.read(PipedInputStream.java:313)
at java.base/java.io.PipedInputStream.read(PipedInputStream.java:380)
at org.eclipse.equinox.internal.p2.transport.ecf.FileReader$1.read(FileReader.java:343)
at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:291)
at java.base/java.io.BufferedInputStream.read1(BufferedInputStream.java:347)
at java.base/java.io.BufferedInputStream.implRead(BufferedInputStream.java:420)
at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:399)
at java.base/java.nio.channels.Channels$ReadableByteChannelImpl.read(Channels.java:316)
at org.eclipse.epp.internal.mpc.core.service.MarketplaceUnmarshaller.peekResponseContent(MarketplaceUnmarshaller.java:98)
at org.eclipse.epp.internal.mpc.core.service.MarketplaceUnmarshaller.unmarshal(MarketplaceUnmarshaller.java:62)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:167)
... 5 more
Contains: Cannot complete request to https://marketplace.eclipse.org/catalogs/api/p: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
org.eclipse.core.runtime.CoreException: Connection failed

This is most often caused by a problem with your internet connection. Please check your internet connection and retry.
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:188)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:128)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:115)
at org.eclipse.epp.internal.mpc.core.service.DefaultCatalogService.listCatalogs(DefaultCatalogService.java:49)
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.lambda$0(AbstractMarketplaceWizardCommand.java:169)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:123)
Caused by: java.io.IOException: Pipe closed
at java.base/java.io.PipedInputStream.read(PipedInputStream.java:313)
at java.base/java.io.PipedInputStream.read(PipedInputStream.java:380)
at org.eclipse.equinox.internal.p2.transport.ecf.FileReader$1.read(FileReader.java:343)
at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:291)
at java.base/java.io.BufferedInputStream.read1(BufferedInputStream.java:347)
at java.base/java.io.BufferedInputStream.implRead(BufferedInputStream.java:420)
at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:399)
at java.base/java.nio.channels.Channels$ReadableByteChannelImpl.read(Channels.java:316)
at org.eclipse.epp.internal.mpc.core.service.MarketplaceUnmarshaller.peekResponseContent(MarketplaceUnmarshaller.java:98)
at org.eclipse.epp.internal.mpc.core.service.MarketplaceUnmarshaller.unmarshal(MarketplaceUnmarshaller.java:62)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:167)
... 5 more
```

I also see this earlier in .metadata/.log:
```
!ENTRY org.eclipse.epp.mpc.core 4 0 2026-03-19 11:15:22.397
!MESSAGE Failed to stream using org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientTransport@20926588 - falling back to org.eclipse.epp.internal.mpc.core.util.TransportFactory$$Lambda/0x000002123af06948@19f1985c: (certificate_unknown) PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
!STACK 1
org.eclipse.core.runtime.CoreException: (certificate_unknown) PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientTransport.stream(HttpClientTransport.java:113)
at org.eclipse.epp.internal.mpc.core.util.FallbackTransportFactory$FallbackTransport.stream(FallbackTransportFactory.java:74)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:162)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:128)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:115)
at org.eclipse.epp.internal.mpc.core.service.DefaultCatalogService.listCatalogs(DefaultCatalogService.java:49)
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.lambda$0(AbstractMarketplaceWizardCommand.java:169)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:123)
Caused by: javax.net.ssl.SSLHandshakeException: (certificate_unknown) PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:130)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:383)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:326)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:321)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1287)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.onConsumeCertificate(CertificateMessage.java:1164)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.consume(CertificateMessage.java:1107)
at java.base/sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:393)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:477)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:448)
at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:206)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:172)
at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1506)
at java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1421)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:455)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:426)
at org.apache.hc.client5.http.ssl.AbstractClientTlsStrategy.executeHandshake(AbstractClientTlsStrategy.java:245)
at org.apache.hc.client5.http.ssl.AbstractClientTlsStrategy.upgrade(AbstractClientTlsStrategy.java:211)
at org.apache.hc.client5.http.ssl.DefaultClientTlsStrategy.upgrade(DefaultClientTlsStrategy.java:48)
at org.apache.hc.client5.http.impl.io.DefaultHttpClientConnectionOperator.upgradeToTls(DefaultHttpClientConnectionOperator.java:263)
at org.apache.hc.client5.http.impl.io.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:227)
at org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:547)
at org.apache.hc.client5.http.impl.classic.InternalExecRuntime.connectEndpoint(InternalExecRuntime.java:164)
at org.apache.hc.client5.http.impl.classic.InternalExecRuntime.connectEndpoint(InternalExecRuntime.java:174)
at org.apache.hc.client5.http.impl.classic.ConnectExec.execute(ConnectExec.java:144)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.ProtocolExec.execute(ProtocolExec.java:195)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.ContentCompressionExec.execute(ContentCompressionExec.java:138)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.HttpRequestRetryExec.execute(HttpRequestRetryExec.java:112)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.RedirectExec.execute(RedirectExec.java:110)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.InternalHttpClient.doExecute(InternalHttpClient.java:185)
at org.apache.hc.client5.http.impl.classic.CloseableHttpClient.execute(CloseableHttpClient.java:106)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientService.execute(HttpClientService.java:87)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientService.execute(HttpClientService.java:79)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.RequestTemplate.execute(RequestTemplate.java:41)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientTransport.stream(HttpClientTransport.java:98)
... 7 more
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:388)
at java.base/sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:271)
at java.base/sun.security.validator.Validator.validate(Validator.java:256)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:230)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:132)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1271)
... 42 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:148)
at java.base/sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:129)
at java.base/java.security.cert.CertPathBuilder.build(CertPathBuilder.java:297)
at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:383)
... 47 more
Contains: (certificate_unknown) PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
javax.net.ssl.SSLHandshakeException: (certificate_unknown) PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:130)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:383)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:326)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:321)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1287)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.onConsumeCertificate(CertificateMessage.java:1164)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.consume(CertificateMessage.java:1107)
at java.base/sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:393)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:477)
at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:448)
at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:206)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:172)
at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1506)
at java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1421)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:455)
at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:426)
at org.apache.hc.client5.http.ssl.AbstractClientTlsStrategy.executeHandshake(AbstractClientTlsStrategy.java:245)
at org.apache.hc.client5.http.ssl.AbstractClientTlsStrategy.upgrade(AbstractClientTlsStrategy.java:211)
at org.apache.hc.client5.http.ssl.DefaultClientTlsStrategy.upgrade(DefaultClientTlsStrategy.java:48)
at org.apache.hc.client5.http.impl.io.DefaultHttpClientConnectionOperator.upgradeToTls(DefaultHttpClientConnectionOperator.java:263)
at org.apache.hc.client5.http.impl.io.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:227)
at org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:547)
at org.apache.hc.client5.http.impl.classic.InternalExecRuntime.connectEndpoint(InternalExecRuntime.java:164)
at org.apache.hc.client5.http.impl.classic.InternalExecRuntime.connectEndpoint(InternalExecRuntime.java:174)
at org.apache.hc.client5.http.impl.classic.ConnectExec.execute(ConnectExec.java:144)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.ProtocolExec.execute(ProtocolExec.java:195)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.ContentCompressionExec.execute(ContentCompressionExec.java:138)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.HttpRequestRetryExec.execute(HttpRequestRetryExec.java:112)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.RedirectExec.execute(RedirectExec.java:110)
at org.apache.hc.client5.http.impl.classic.ExecChainElement.execute(ExecChainElement.java:51)
at org.apache.hc.client5.http.impl.classic.InternalHttpClient.doExecute(InternalHttpClient.java:185)
at org.apache.hc.client5.http.impl.classic.CloseableHttpClient.execute(CloseableHttpClient.java:106)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientService.execute(HttpClientService.java:87)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientService.execute(HttpClientService.java:79)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.RequestTemplate.execute(RequestTemplate.java:41)
at org.eclipse.epp.internal.mpc.core.transport.httpclient.HttpClientTransport.stream(HttpClientTransport.java:98)
at org.eclipse.epp.internal.mpc.core.util.FallbackTransportFactory$FallbackTransport.stream(FallbackTransportFactory.java:74)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:162)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:128)
at org.eclipse.epp.internal.mpc.core.service.RemoteMarketplaceService.processRequest(RemoteMarketplaceService.java:115)
at org.eclipse.epp.internal.mpc.core.service.DefaultCatalogService.listCatalogs(DefaultCatalogService.java:49)
at org.eclipse.epp.internal.mpc.ui.commands.AbstractMarketplaceWizardCommand.lambda$0(AbstractMarketplaceWizardCommand.java:169)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:123)
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:388)
at java.base/sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:271)
at java.base/sun.security.validator.Validator.validate(Validator.java:256)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:230)
at java.base/sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:132)
at java.base/sun.security.ssl.CertificateMessage$T13CertificateConsumer.checkServerCerts(CertificateMessage.java:1271)
... 42 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:148)
at java.base/sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:129)
at java.base/java.security.cert.CertPathBuilder.build(CertPathBuilder.java:297)
at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:383)
... 47 more
```

## Tested under this environment:
* OS & version: Windows 11 23H2
* Eclipse IDE/Platform version (as shown in *Help > About*): both 2025-12 (4.38.0) and 2026-03 (4.39.0)

## Community

- [x] I understand reporting an issue to this OSS project does not mandate anyone to fix it. Other contributors may consider the issue, or not, at their own convenience. The most efficient way to get it fixed is that I fix it myself and contribute it back as a good quality patch to the project.