Add nil to references to mark as ready to be GC'd

This is a POC to understand why memory isn't being deallocated normally
without having to do this.

common/browser.go

@@ -223,6 +223,19 @@ func (b *Browser) initEvents() error { //nolint:cyclop
 			if b.vuCtxCancelFn != nil {
 				b.vuCtxCancelFn()
 			}
+
+			go func() {
+				<-b.browserCtx.Done()
+
+				b.browserProc = nil
+				b.browserOpts = nil
+				b.conn = nil
+				b.context = nil
+				b.defaultContext = nil
+				b.pages = nil
+				b.sessionIDtoTargetID = nil
+				b.logger = nil
+			}()
 		}()
 		for {
 			select {

common/browser_context.go

@@ -120,6 +120,17 @@ func NewBrowserContext(
 		return nil, fmt.Errorf("adding web vital init script to new browser context: %w", err)
 	}
 
+	go func() {
+		<-b.ctx.Done()
+
+		b.browser = nil
+		b.opts = nil
+		b.timeoutSettings = nil
+		b.logger = nil
+		b.vu = nil
+		b.evaluateOnNewDocumentSources = nil
+	}()
+
 	return &b, nil
 }
 

common/connection.go

@@ -201,6 +201,17 @@ func (c *Connection) close(code int) error {
 			// Stop the main control loop
 			close(c.done)
 			_ = c.conn.Close()
+
+			go func() {
+				<-c.ctx.Done()
+
+				c.cancelCtx = nil
+				c.logger = nil
+				c.conn = nil
+				c.msgIDGen = nil
+				c.sessions = nil
+				c.onTargetAttachedToTarget = nil
+			}()
 		}()
 
 		c.closeAllSessions()

common/frame_manager.go

@@ -66,6 +66,19 @@ func NewFrameManager(
 		id:              atomic.AddInt64(&frameManagerID, 1),
 	}
 
+	go func() {
+		<-m.ctx.Done()
+
+		m.session = nil
+		m.page = nil
+		m.timeoutSettings = nil
+		m.mainFrame = nil
+		m.frames = nil
+		m.barriers = nil
+		m.vu = nil
+		m.logger = nil
+	}()
+
 	m.logger.Debugf("FrameManager:New", "fmid:%d", m.ID())
 
 	return m

common/frame_session.go

@@ -236,6 +236,24 @@ func (fs *FrameSession) initEvents() {
 	}
 
 	go func() {
+		go func() {
+			<-fs.ctx.Done()
+
+			fs.session = nil
+			fs.page = nil
+			fs.parent = nil
+			fs.manager = nil
+			fs.networkManager = nil
+			fs.k6Metrics = nil
+			fs.contextIDToContext = nil
+			fs.isolatedWorlds = nil
+			fs.eventCh = nil
+			fs.childSessions = nil
+			fs.vu = nil
+			fs.logger = nil
+			fs.mainFrameSpan = nil
+		}()
+
 		fs.logger.Debugf("NewFrameSession:initEvents:go",
 			"sid:%v tid:%v", fs.session.ID(), fs.targetID)
 		defer func() {

common/network_manager.go

@@ -378,6 +378,23 @@ func (m *NetworkManager) initEvents() {
 }
 
 func (m *NetworkManager) handleEvents(in <-chan Event) bool {
+	go func() {
+		<-m.ctx.Done()
+
+		m.logger = nil
+		m.session = nil
+		m.parent = nil
+		m.frameManager = nil
+		m.credentials = nil
+		m.resolver = nil
+		m.vu = nil
+		m.customMetrics = nil
+		m.mi = nil
+		m.reqIDToRequest = nil
+		m.attemptedAuth = nil
+		m.extraHTTPHeaders = nil
+	}()
+
 	select {
 	case <-m.ctx.Done():
 		return false

common/page.go

@@ -348,6 +348,29 @@ func (p *Page) initEvents() {
 		defer func() {
 			p.logger.Debugf("Page:initEvents:go:return",
 				"sid:%v tid:%v", p.session.ID(), p.targetID)
+
+			go func() {
+				<-p.ctx.Done()
+
+				p.Keyboard = nil
+				p.Mouse = nil
+				p.Touchscreen = nil
+				p.session = nil
+				p.browserCtx = nil
+				p.opener = nil
+				p.frameManager = nil
+				p.timeoutSettings = nil
+				p.emulatedSize = nil
+				p.extraHTTPHeaders = nil
+				p.eventCh = nil
+				p.eventHandlers = nil
+				p.mainFrameSession = nil
+				p.frameSessions = nil
+				p.workers = nil
+				p.routes = nil
+				p.vu = nil
+				p.logger = nil
+			}()
 		}()
 
 		for {

common/session.go

@@ -70,6 +70,11 @@ func (s *Session) close() {
 	s.closed = true
 
 	s.emit(EventSessionClosed, nil)
+
+	go func() {
+		<-s.ctx.Done()
+		s.conn = nil
+	}()
 }
 
 func (s *Session) markAsCrashed() {