diff --git a/go.mod b/go.mod
index 6d95b22..08474f3 100644
--- a/go.mod
+++ b/go.mod
@@ -9,3 +9,6 @@ require (
 	github.com/google/go-cmp v0.3.0
 	github.com/sourcegraph/jsonrpc2 v0.2.0
 )
+
+// TODO: merge github.com/fhs/go-lsp-internal PR, update dependency and delete next line
+replace github.com/fhs/go-lsp-internal => github.com/cloudspinner/go-lsp-internal v0.0.0-20240109201957-d9537c30fb78
diff --git a/go.sum b/go.sum
index 180cdf4..32b81b4 100644
--- a/go.sum
+++ b/go.sum
@@ -1,19 +1,12 @@
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/cloudspinner/go-lsp-internal v0.0.0-20240109201957-d9537c30fb78 h1:W/QXjKTNneGNXhD+wDd0DBso2NDjl4cAakUa9+8cf2w=
+github.com/cloudspinner/go-lsp-internal v0.0.0-20240109201957-d9537c30fb78/go.mod h1:GF34TbXJNatquGdvhieClRATyP8RFzX+l+rNYqfdTow=
 github.com/fhs/9fans-go v0.0.0-fhs.20200606 h1:kwqns/76paQLNLDx9I5UFkFG1z1tSqHq8a3j/I0kLr4=
 github.com/fhs/9fans-go v0.0.0-fhs.20200606/go.mod h1:9PelHyep+qBAEyYdGnqAa66ZGjWE0L8EJP+GIDz8p7M=
-github.com/fhs/go-lsp-internal v0.0.0-20230610234852-c5f2102def33 h1:IOmTt60Dzfdp4NYvkrOB9AotLk7mBYtd+PBsU5jAQeg=
-github.com/fhs/go-lsp-internal v0.0.0-20230610234852-c5f2102def33/go.mod h1:GF34TbXJNatquGdvhieClRATyP8RFzX+l+rNYqfdTow=
-github.com/fhs/go-lsp-internal v0.0.0-20230617125605-15c355072be4 h1:3viom14iPcmgEM8hyWJEc7gHAW3HCNUO38bgHYsFaqE=
-github.com/fhs/go-lsp-internal v0.0.0-20230617125605-15c355072be4/go.mod h1:GF34TbXJNatquGdvhieClRATyP8RFzX+l+rNYqfdTow=
-github.com/fhs/go-lsp-internal v0.0.0-20230617170009-e3a916438ee1 h1:jeF/D2AKXTooLP6m1DP9Qd9dSRmUt2h5VN+3qyyMlII=
-github.com/fhs/go-lsp-internal v0.0.0-20230617170009-e3a916438ee1/go.mod h1:GF34TbXJNatquGdvhieClRATyP8RFzX+l+rNYqfdTow=
-github.com/fhs/go-lsp-internal v0.0.0-20230619000151-7826e273203a h1:4qLe7eMLgsA82mUUBVmSyOrCE0UV989Oxsqgd+PQcOk=
-github.com/fhs/go-lsp-internal v0.0.0-20230619000151-7826e273203a/go.mod h1:GF34TbXJNatquGdvhieClRATyP8RFzX+l+rNYqfdTow=
 github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/sourcegraph/jsonrpc2 v0.2.0 h1:KjN/dC4fP6aN9030MZCJs9WQbTOjWHhrtKVpzzSrr/U=
 github.com/sourcegraph/jsonrpc2 v0.2.0/go.mod h1:ZafdZgk/axhT1cvZAPOhw+95nz2I/Ra5qMlU4gTRwIo=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
diff --git a/internal/lsp/acmelsp/acmelsp.go b/internal/lsp/acmelsp/acmelsp.go
index 539c41b..7bc7543 100644
--- a/internal/lsp/acmelsp/acmelsp.go
+++ b/internal/lsp/acmelsp/acmelsp.go
@@ -219,6 +219,32 @@ func CodeActionAndFormat(ctx context.Context, server FormatServer, doc *protocol
 	return nil
 }
 
+func orsToEdits(ors []protocol.Or_TextDocumentEdit_edits_Elem) []protocol.TextEdit {
+	edits := make([]protocol.TextEdit, len(ors))
+	for i, or := range ors {
+		switch or.Value.(type) {
+		case protocol.AnnotatedTextEdit:
+			edits[i] = or.Value.(protocol.AnnotatedTextEdit).TextEdit
+		case protocol.TextEdit:
+			edits[i] = or.Value.(protocol.TextEdit)
+		case nil:
+			edits[i] = protocol.TextEdit{}
+		}
+	}
+	return edits
+}
+
+func executeCommand(ctx context.Context, server FormatServer, doc *protocol.TextDocumentIdentifier, c *protocol.Command) error {
+	_, err := server.ExecuteCommandOnDocument(ctx, &proxy.ExecuteCommandOnDocumentParams{
+		TextDocument: *doc,
+		ExecuteCommandParams: protocol.ExecuteCommandParams{
+			Command:   c.Command,
+			Arguments: c.Arguments,
+		},
+	})
+	return err
+}
+
 func editWorkspace(we *protocol.WorkspaceEdit) error {
 	if we == nil {
 		return nil // no changes to apply
@@ -230,7 +256,7 @@ func editWorkspace(we *protocol.WorkspaceEdit) error {
 		changes := make(map[protocol.DocumentURI][]protocol.TextEdit)
 		for _, dc := range we.DocumentChanges {
 			if tde := dc.TextDocumentEdit; tde != nil {
-				changes[tde.TextDocument.TextDocumentIdentifier.URI] = tde.Edits
+				changes[tde.TextDocument.TextDocumentIdentifier.URI] = orsToEdits(tde.Edits)
 			}
 		}
 		we.Changes = changes
diff --git a/internal/lsp/acmelsp/client.go b/internal/lsp/acmelsp/client.go
index b94b721..c304028 100644
--- a/internal/lsp/acmelsp/client.go
+++ b/internal/lsp/acmelsp/client.go
@@ -155,8 +155,8 @@ func (c *Client) init(conn net.Conn, cfg *ClientConfig) error {
 			Capabilities: protocol.ClientCapabilities{
 				TextDocument: protocol.TextDocumentClientCapabilities{
 					CodeAction: protocol.CodeActionClientCapabilities{
-						CodeActionLiteralSupport: protocol.PCodeActionLiteralSupportPCodeAction{
-							CodeActionKind: protocol.FCodeActionKindPCodeActionLiteralSupport{
+						CodeActionLiteralSupport: protocol.ClientCodeActionLiteralOptions{
+							CodeActionKind: protocol.ClientCodeActionKindOptions{
 								ValueSet: []protocol.CodeActionKind{
 									protocol.SourceOrganizeImports,
 								},
@@ -167,8 +167,8 @@ func (c *Client) init(conn net.Conn, cfg *ClientConfig) error {
 						HierarchicalDocumentSymbolSupport: true,
 					},
 					Completion: protocol.CompletionClientCapabilities{
-						CompletionItem: protocol.PCompletionItemPCompletion{
-							TagSupport: protocol.FTagSupportPCompletionItem{
+						CompletionItem: protocol.ClientCompletionItemOptions{
+							TagSupport: &protocol.CompletionItemTagOptions{
 								ValueSet: []protocol.CompletionItemTag{},
 							},
 						},
diff --git a/internal/lsp/acmelsp/client_test.go b/internal/lsp/acmelsp/client_test.go
index a563581..b1f1ad4 100644
--- a/internal/lsp/acmelsp/client_test.go
+++ b/internal/lsp/acmelsp/client_test.go
@@ -191,17 +191,21 @@ func main() {
 			if err != nil {
 				t.Fatalf("Definition failed: %v", err)
 			}
-			want := []protocol.Location{
-				{
-					URI: uri,
-					Range: protocol.Range{
-						Start: protocol.Position{
-							Line:      4,
-							Character: 5,
-						},
-						End: protocol.Position{
-							Line:      4,
-							Character: 10,
+			want := &protocol.Or_Result_textDocument_definition{
+				Value: protocol.Definition{
+					Value: []protocol.Location{
+						{
+							URI: uri,
+							Range: protocol.Range{
+								Start: protocol.Position{
+									Line:      4,
+									Character: 5,
+								},
+								End: protocol.Position{
+									Line:      4,
+									Character: 10,
+								},
+							},
 						},
 					},
 				},
diff --git a/internal/lsp/acmelsp/proxy.go b/internal/lsp/acmelsp/proxy.go
index 40eab15..7afee93 100644
--- a/internal/lsp/acmelsp/proxy.go
+++ b/internal/lsp/acmelsp/proxy.go
@@ -48,7 +48,7 @@ func (s *proxyServer) DidChangeWorkspaceFolders(ctx context.Context, params *pro
 	return s.ss.DidChangeWorkspaceFolders(ctx, params.Event.Added, params.Event.Removed)
 }
 
-func (s *proxyServer) Completion(ctx context.Context, params *protocol.CompletionParams) (*protocol.CompletionList, error) {
+func (s *proxyServer) Completion(ctx context.Context, params *protocol.CompletionParams) (*protocol.Or_Result_textDocument_completion, error) {
 	srv, err := serverForURI(s.ss, params.TextDocumentPositionParams.TextDocument.URI)
 	if err != nil {
 		return nil, fmt.Errorf("Completion: %v", err)
@@ -56,7 +56,7 @@ func (s *proxyServer) Completion(ctx context.Context, params *protocol.Completio
 	return srv.Client.Completion(ctx, params)
 }
 
-func (s *proxyServer) Definition(ctx context.Context, params *protocol.DefinitionParams) ([]protocol.Location, error) {
+func (s *proxyServer) Definition(ctx context.Context, params *protocol.DefinitionParams) (*protocol.Or_Result_textDocument_definition, error) {
 	srv, err := serverForURI(s.ss, params.TextDocumentPositionParams.TextDocument.URI)
 	if err != nil {
 		return nil, fmt.Errorf("Definition: %v", err)
diff --git a/internal/lsp/acmelsp/remote.go b/internal/lsp/acmelsp/remote.go
index b81456b..5ff6253 100644
--- a/internal/lsp/acmelsp/remote.go
+++ b/internal/lsp/acmelsp/remote.go
@@ -99,8 +99,18 @@ func (rc *RemoteCmd) Completion(ctx context.Context, kind CompletionKind) error
 		return err
 	}
 
-	if (kind == CompleteInsertFirstMatch && len(result.Items) >= 1) || (kind == CompleteInsertOnlyMatch && len(result.Items) == 1) {
-		textEdit := result.Items[0].TextEdit
+	var items []protocol.CompletionItem
+	switch val := result.Value; val.(type) {
+	case protocol.CompletionList:
+		items = val.(protocol.CompletionList).Items
+	case []protocol.CompletionItem:
+		items = val.([]protocol.CompletionItem)
+	default:
+		return fmt.Errorf("unknown Completion result type: %T", val)
+	}
+
+	if (kind == CompleteInsertFirstMatch && len(items) >= 1) || (kind == CompleteInsertOnlyMatch && len(items) == 1) {
+		textEdit := items[0].TextEdit
 		if textEdit == nil {
 			// TODO(fhs): Use insertText or label instead.
 			return fmt.Errorf("nil TextEdit in completion item")
@@ -109,18 +119,18 @@ func (rc *RemoteCmd) Completion(ctx context.Context, kind CompletionKind) error
 			return fmt.Errorf("failed to apply completion edit: %v", err)
 		}
 
-		if len(result.Items) == 1 {
+		if len(items) == 1 {
 			return nil
 		}
 	}
 
 	var sb strings.Builder
 
-	if len(result.Items) == 0 {
+	if len(items) == 0 {
 		fmt.Fprintf(&sb, "no completion\n")
 	}
 
-	for _, item := range result.Items {
+	for _, item := range items {
 		fmt.Fprintf(&sb, "%v\t%v\n", item.Label, item.Detail)
 	}
 
@@ -151,12 +161,33 @@ func (rc *RemoteCmd) Definition(ctx context.Context, print bool) error {
 	if err != nil {
 		return fmt.Errorf("failed to get position: %v", err)
 	}
-	locations, err := rc.server.Definition(ctx, &protocol.DefinitionParams{
+	orResultDef, err := rc.server.Definition(ctx, &protocol.DefinitionParams{
 		TextDocumentPositionParams: *pos,
 	})
 	if err != nil {
 		return fmt.Errorf("bad server response: %v", err)
 	}
+	var locations []protocol.Location
+	switch val := orResultDef.Value; val.(type) {
+	case protocol.Definition:
+		switch orDefVal := val.(protocol.Definition).Value; orDefVal.(type) {
+		case protocol.Location:
+			locations = []protocol.Location{orDefVal.(protocol.Location)}
+		case []protocol.Location:
+			locations = orDefVal.([]protocol.Location)
+		default:
+			return fmt.Errorf("unknown Definition location type: %T", orDefVal)
+		}
+	case []protocol.DefinitionLink:
+		links := val.([]protocol.DefinitionLink)
+		locs := make([]protocol.Location, len(links))
+		for i, link := range links {
+			locs[i] = protocol.Location{link.TargetURI, link.TargetSelectionRange}
+		}
+		locations = locs
+	default:
+		return fmt.Errorf("unknown Definition result type: %T", val)
+	}
 	if print {
 		return PrintLocations(rc.Stdout, locations)
 	}
diff --git a/internal/lsp/proxy/client.go b/internal/lsp/proxy/client.go
index d82f923..81fabf4 100644
--- a/internal/lsp/proxy/client.go
+++ b/internal/lsp/proxy/client.go
@@ -99,6 +99,11 @@ func (c *NotImplementedClient) DiagnosticRefresh(context.Context) error {
 	return fmt.Errorf("workspace/diagnostic/refresh not implemented")
 }
 
+// workspace/foldingRange/refresh
+func (c *NotImplementedClient) FoldingRangeRefresh(context.Context) error {
+	return fmt.Errorf("workspace/foldingRange/refresh not implemented")
+}
+
 // workspace/inlayHint/refresh
 func (c *NotImplementedClient) InlayHintRefresh(context.Context) error {
 	return fmt.Errorf("workspace/inlayHint/refresh not implemented")
diff --git a/internal/lsp/proxy/server.go b/internal/lsp/proxy/server.go
index b63f249..eb1ef78 100644
--- a/internal/lsp/proxy/server.go
+++ b/internal/lsp/proxy/server.go
@@ -182,13 +182,13 @@ func (s *NotImplementedServer) CodeLens(context.Context, *protocol.CodeLensParam
 func (s *NotImplementedServer) ColorPresentation(context.Context, *protocol.ColorPresentationParams) ([]protocol.ColorPresentation, error) {
 	return nil, fmt.Errorf("not implemented")
 }
-func (s *NotImplementedServer) Completion(context.Context, *protocol.CompletionParams) (*protocol.CompletionList, error) {
+func (s *NotImplementedServer) Completion(context.Context, *protocol.CompletionParams) (*protocol.Or_Result_textDocument_completion, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 func (s *NotImplementedServer) Declaration(context.Context, *protocol.DeclarationParams) (*protocol.Or_textDocument_declaration, error) {
 	return nil, fmt.Errorf("not implemented")
 }
-func (s *NotImplementedServer) Definition(context.Context, *protocol.DefinitionParams) ([]protocol.Location, error) {
+func (s *NotImplementedServer) Definition(context.Context, *protocol.DefinitionParams) (*protocol.Or_Result_textDocument_definition, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 func (s *NotImplementedServer) Diagnostic(context.Context, *string) (*string, error) {
@@ -233,6 +233,9 @@ func (s *NotImplementedServer) Implementation(context.Context, *protocol.Impleme
 func (s *NotImplementedServer) InlayHint(context.Context, *protocol.InlayHintParams) ([]protocol.InlayHint, error) {
 	return nil, fmt.Errorf("not implemented")
 }
+func (s *NotImplementedServer) InlineCompletion(context.Context, *protocol.InlineCompletionParams) (*protocol.Or_Result_textDocument_inlineCompletion, error) {
+	return nil, fmt.Errorf("not implemented")
+}
 func (s *NotImplementedServer) InlineValue(context.Context, *protocol.InlineValueParams) ([]protocol.InlineValue, error) {
 	return nil, fmt.Errorf("not implemented")
 }
@@ -248,7 +251,7 @@ func (s *NotImplementedServer) OnTypeFormatting(context.Context, *protocol.Docum
 func (s *NotImplementedServer) PrepareCallHierarchy(context.Context, *protocol.CallHierarchyPrepareParams) ([]protocol.CallHierarchyItem, error) {
 	return nil, fmt.Errorf("not implemented")
 }
-func (s *NotImplementedServer) PrepareRename(context.Context, *protocol.PrepareRenameParams) (*protocol.PrepareRename2Gn, error) {
+func (s *NotImplementedServer) PrepareRename(context.Context, *protocol.PrepareRenameParams) (*protocol.PrepareRenameResult, error) {
 	return nil, fmt.Errorf("not implemented")
 }
 func (s *NotImplementedServer) PrepareTypeHierarchy(context.Context, *protocol.TypeHierarchyPrepareParams) ([]protocol.TypeHierarchyItem, error) {
@@ -257,6 +260,9 @@ func (s *NotImplementedServer) PrepareTypeHierarchy(context.Context, *protocol.T
 func (s *NotImplementedServer) RangeFormatting(context.Context, *protocol.DocumentRangeFormattingParams) ([]protocol.TextEdit, error) {
 	return nil, fmt.Errorf("not implemented")
 }
+func (s *NotImplementedServer) RangesFormatting(context.Context, *protocol.DocumentRangesFormattingParams) ([]protocol.TextEdit, error) {
+	return nil, fmt.Errorf("not implemented")
+}
 func (s *NotImplementedServer) References(context.Context, *protocol.ReferenceParams) ([]protocol.Location, error) {
 	return nil, fmt.Errorf("not implemented")
 }