Change:
return nls.localize('postUpdateTooltip', "Please reload Visual Studio Code to enable the updated extension."); } <del> const extensionInOtherServer = this.installed.filter(e => areSameExtensions(e.identifier, extension!.identifier) && e.server !== extension!.server)[0]; if (extensionInOtherServer) { // This extension prefers to run on UI/Local side but is running in remote if (runningExtensionServer === this.extensionManagementServerService.remoteExtensionManagementServer && this.extensionManifestPropertiesService.prefersExecuteOnUI(extension.local!.manifest) && extensionInOtherServer.server === this.extensionManagementServerService.localExtensionManagementServer) { return nls.localize('enable locally', "Please reload Visual Studio Code to enable this extension locally."); } </del> <ins> if (this.extensionsServers.length > 1) { const extensionInOtherServer = this.installed.filter(e => areSameExtensions(e.identifier, extension!.identifier) && e.server !== extension!.server)[0]; if (extensionInOtherServer) { // This extension prefers to run on UI/Local side but is running in remote if (runningExtensionServer === this.extensionManagementServerService.remoteExtensionManagementServer && this.extensionManifestPropertiesService.prefersExecuteOnUI(extension.local!.manifest) && extensionInOtherServer.server === this.extensionManagementServerService.localExtensionManagementServer) { return nls.localize('enable locally', "Please reload Visual Studio Code to enable this extension locally."); } </ins> <del> // This extension prefers to run on Workspace/Remote side but is running in local if (runningExtensionServer === this.extensionManagementServerService.localExtensionManagementServer && this.extensionManifestPropertiesService.prefersExecuteOnWorkspace(extension.local!.manifest) && extensionInOtherServer.server === this.extensionManagementServerService.remoteExtensionManagementServer) { return nls.localize('enable remote', "Please reload Visual Studio Code to enable this extension in {0}.", this.extensionManagementServerService.remoteExtensionManagementServer?.label); </del> <ins> // This extension prefers to run on Workspace/Remote side but is running in local if (runningExtensionServer === this.extensionManagementServerService.localExtensionManagementServer && this.extensionManifestPropertiesService.prefersExecuteOnWorkspace(extension.local!.manifest) && extensionInOtherServer.server === this.extensionManagementServerService.remoteExtensionManagementServer) { return nls.localize('enable remote', "Please reload Visual Studio Code to enable this extension in {0}.", this.extensionManagementServerService.remoteExtensionManagementServer?.label); } </ins> } }

Discussion:
re The automatic perf monitoring has shown a high number of calls to . This means the call/function itself is slow or it is called at a very high rate (so that the profiler always sees it running) The most common stacktrace via which this is reported comes through .
/duplicate
Thanks for creating this issue! We figured it's covering the same as another one we already have. Thus, we closed this one as a duplicate. You can search for . See also our . Happy Coding!
I don't think this is a dupe because the callstack comes in via which I don't see in the other trace
But I think the root cause is same for both that is slow as mentioned in the summary of the other issue. Hence I marked it as duplicate.
Pfff - that would mean it is catastrophically slow. My suspicion is that it is just slow but that comes in combination with being over eagerly called? Maybe some event leakage or some over eager calling through some other means. This symptom might disappear when has become fast but I think we need to understand why it ends up on a hot code path in the first place
Will investigate why this is being eagerly called too.