fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot

[Copilot]

When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.

Changes

• screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.

await response.addFileResult(resolvedFile, data);
if (!params.filename)
  await response.registerImageResult(data, fileType);

• screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.

Behavior

filename param	Image in MCP response
omitted	✅ included (LLM can see it)
'' (empty string)	✅ included (treated as auto-generate)
"output.png"	❌ omitted (file saved to disk only)

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• accounts.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
• clients2.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
• safebrowsingohttpgateway.googleapis.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
• www.google.com
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)