I had to rebuild the addon myself as 4.1.x was staying at “Waiting”… Anyway, here is my debug output, maybe you could amend the error logs or the README with a hint that a higher number of threads might be necessary?
I don’t understand why the bridge would have no bridgeUID() in this case though, but I don’t have to understand everything 
Now that I’m looking at my older config files, we had a similar thread with 3.x as well:
2023-08-16 12:01:01.607 [DEBUG] [nal.handler.SomfyTahomaBridgeHandler] - Cannot start http client for: somfytahoma:bridge:bcaeba8966
java.lang.IllegalStateException: Insufficient configured threads: required=12 < max=10 for QueuedThreadPool[OH-httpClient-somfytahom-e9f43da6]@466a057e{STOPPED,5<=0<=10,i=0,r=-1,q=0}[NO_TRY]
at org.eclipse.jetty.util.thread.ThreadPoolBudget.check(ThreadPoolBudget.java:165) ~[?:?]
at org.eclipse.jetty.util.thread.ThreadPoolBudget.leaseTo(ThreadPoolBudget.java:141) ~[?:?]
at org.eclipse.jetty.util.thread.ThreadPoolBudget.leaseFrom(ThreadPoolBudget.java:191) ~[?:?]
at org.eclipse.jetty.io.SelectorManager.doStart(SelectorManager.java:255) ~[?:?]
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:73) ~[?:?]
at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) ~[?:?]
at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:117) ~[?:?]
at org.eclipse.jetty.client.AbstractConnectorHttpClientTransport.doStart(AbstractConnectorHttpClientTransport.java:64) ~[?:?]
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:73) ~[?:?]
at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:169) ~[?:?]
at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:117) ~[?:?]
at org.eclipse.jetty.client.HttpClient.doStart(HttpClient.java:258) ~[?:?]
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:73) ~[?:?]
at org.openhab.binding.somfytahoma.internal.handler.SomfyTahomaBridgeHandler.createHttpClient(SomfyTahomaBridgeHandler.java:196) ~[?:?]
at org.openhab.binding.somfytahoma.internal.handler.SomfyTahomaBridgeHandler.initialize(SomfyTahomaBridgeHandler.java:177) ~[?:?]
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[?:?]
at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
at java.lang.reflect.Method.invoke(Method.java:568) ~[?:?]
at org.openhab.core.internal.common.AbstractInvocationHandler.invokeDirect(AbstractInvocationHandler.java:147) ~[?:?]
at org.openhab.core.internal.common.Invocation.call(Invocation.java:52) ~[?:?]
at java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[?:?]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) ~[?:?]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) ~[?:?]
at java.lang.Thread.run(Thread.java:833) ~[?:?]