Feature/kuba nowakowski/home preload

[sumo-slonik]

Explanation of Change

Adding a preload mechanism to the inbox tab, which improves the user experience when switching between tabs.

main.mp4

Fixed Issues

$ #72122
$ #71587
PROPOSAL:

Tests

Test Steps:

1. Launch the application.
2. Navigate sequentially through the following tabs:
   2.1. Reports
   2.2. Workspaces (including opening a specific workspace view and selecting a report that redirects to the Inbox)
   2.3. Account
   From each of these tabs, go to the Inbox tab.
3. Verify that the Inbox is displayed correctly each time.
4. Navigate again to the Reports tab.
5. Clear the search field if necessary.
6. Type a search query, e.g. "merchant:coffee" or "type:chat Hi", and press Enter.
7. Click on the Inbox icon
8. Click the Search icon and observe the search results list.

Expected Result:

• The Inbox view is displayed correctly when accessed from all tabs.
• The performed search is displayed properly in inbox

• Verify that no errors appear in the JS console

Offline tests

unnesesary

QA Steps

same as test

// TODO: These must be filled out, or the issue title must include "[No QA]."

• Verify that no errors appear in the JS console

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
  • MacOS: Desktop
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I verified there are no new alerts related to the canBeMissing param for useOnyx
• I followed proper code patterns (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product is localized by adding it to src/languages/* files and using the translation method
    • If any non-english text was added/modified, I used JaimeGPT to get English > Spanish translation. I then posted it in #expensify-open-source and it was approved by an internal Expensify engineer. Link to Slack message:
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.ts or at the top of the file that uses the constant) are defined as such
• I verified that if a function's arguments changed that all usages have also been updated correctly
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG))
• If new assets were added or existing ones were modified, I verified that:
  • The assets are optimized and compressed (for SVG files, run npm run compress-svg)
  • The assets load correctly across all supported platforms.
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• I added unit tests for any new feature or bug fix in this PR to help automatically prevent regressions in this user flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.

Screenshots/Videos

Android: mWeb Chrome

Screen.Recording.2025-10-23.at.10.08.15.mov

iOS: Native

branch.mov

iOS: mWeb Safari

Screen.Recording.2025-10-23.at.09.53.02.mov

MacOS: Chrome / Safari

Screen.Recording.2025-10-22.at.15.11.29.mov

MacOS: Desktop

Screen.Recording.2025-10-23.at.10.13.51.mov

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...c/components/Navigation/NavigationTabBar/index.tsx	0.00%	1 Missing ⚠️

Files with missing lines	Coverage Δ
...ion/AppNavigator/usePreloadFullScreenNavigators.ts	17.24% <100.00%> (ø)
...c/components/Navigation/NavigationTabBar/index.tsx	56.43% <0.00%> (-0.57%)	⬇️

... and 73 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[melvin-bot]

@linhvovan29546 Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[linhvovan29546]

I'm just testing on the iOS simulator, it seems faster when switching between the Inbox and Account tabs

[WojtekBoman]

LGTM!

[mountiny]

@WojtekBoman What were the issues due to which we did not enable it in a first place? I think there were some blockers, are those all addressed here? Can we add the tests steps to the PR?

@Ollyws Since you had been reviewing the original preloading feature, can you continue the review here please

[mountiny]

@sumo-slonik can you please leave performance metrics comparing before and after using the heavy copilot account SWM got access to (cc @blazejkustra)

Lets please do that on all performance PRs to compare the before and after with numbers

[github-actions]

🚧 @mountiny has triggered a test Expensify/App build. You can view the workflow run here.

[github-actions]

🧪🧪 Use the links below to test this adhoc build on Android, iOS, Desktop, and Web. Happy testing! 🧪🧪
Built from App PR #73218.

Android 🤖	iOS 🍎
https://ad-hoc-expensify-cash.s3.amazonaws.com/android/73218/index.html	https://ad-hoc-expensify-cash.s3.amazonaws.com/ios/73218/index.html

Desktop 💻	Web 🕸️
https://ad-hoc-expensify-cash.s3.amazonaws.com/desktop/73218/NewExpensify.dmg	https://73218.pr-testing.expensify.com

---

👀 View the workflow run that generated this build 👀

[sumo-slonik]

@WojtekBoman What were the issues due to which we did not enable it in a first place? I think there were some blockers, are those all addressed here? Can we add the tests steps to the PR?

While testing this PR, it seems that I’ve managed to get through the bugs that appeared earlier. Later today I’ll also add to the test steps the scenarios from the issues that were problematic before, and link the related bug issues.

[sumo-slonik]

@sumo-slonik can you please leave performance metrics comparing before and after using the heavy copilot account SWM got access to (cc @blazejkustra)

Lets please do that on all performance PRs to compare the before and after with numbers

Today I worked all day on the search tab preload, and I ran into a few issues that I wanted to tackle fresh. I’ll take care of them first thing tomorrow morning.

[sumo-slonik]

@mountiny As I mentioned earlier, the performance gain from the preload is best illustrated in the attached recording, the profiler results don’t fully reflect the actual improvement.
What’s shown in the video consistently reproduces across multiple runs (the exact numbers vary slightly, but the overall trend is stable).

Here are the averaged results from several attempts:

main| account → inbox: 2.09s

with preload enabled| account → inbox: 0.47s

I’ve attached a slow-motion video for clarity.
All tests were performed on the aplauseTester account, where I observed these results.

main_1.mp4

[mountiny]

@aimane-chnaif please go ahead with the review

[aimane-chnaif]

Testing all these regressions which were fixed by disable preloading for Inbox and Reports tabs:

• iOS - Reports - Reports load infinitely when opening for first time after creating account #69812
• Reports - "0 selected" displayed on "Reports" after deleting expenses on chat. #69741
• Reports - After switching tab and back to Reports, the selected expense is not selected #69816

Result: not reproducible

69741.mov

69812.mov

69816.mov

[aimane-chnaif]

Reviewer Checklist

• I have verified the author checklist is complete (all boxes are checked off).
• I verified the correct issue is linked in the ### Fixed Issues section above
• I verified testing steps are clear and they cover the changes made in this PR
  • I verified the steps for local testing are in the Tests section
  • I verified the steps for Staging and/or Production testing are in the QA steps section
  • I verified the steps cover any possible failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
• I checked that screenshots or videos are included for tests on all platforms
• I included screenshots or videos for tests on all platforms
• I verified that the composer does not automatically focus or open the keyboard on mobile unless explicitly intended. This includes checking that returning the app from the background does not unexpectedly open the keyboard.
• I verified tests pass on all platforms & I tested again on:
  • Android: HybridApp
  • Android: mWeb Chrome
  • iOS: HybridApp
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
  • MacOS: Desktop
• If there are any errors in the console that are unrelated to this PR, I either fixed them (preferred) or linked to where I reported them in Slack
• I verified there are no new alerts related to the canBeMissing param for useOnyx
• I verified proper code patterns were followed (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick).
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product is localized by adding it to src/languages/* files and using the translation method
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I verified that this PR follows the guidelines as stated in the Review Guidelines
• I verified other components that can be impacted by these changes have been tested, and I retested again (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar have been tested & I retested again)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.ts or at the top of the file that uses the constant) are defined as such
• If a new component is created I verified that:
  • A similar component doesn't exist in the codebase
  • All props are defined accurately and each prop has a /** comment above it */
  • The file is named correctly
  • The component has a clear name that is non-ambiguous and the purpose of the component can be inferred from the name alone
  • The only data being stored in the state is data necessary for rendering and nothing else
  • For Class Components, any internal methods passed to components event handlers are bound to this properly so there are no scoping issues (i.e. for onClick={this.submit} the method this.submit should be bound to this in the constructor)
  • Any internal methods bound to this are necessary to be bound (i.e. avoid this.submit = this.submit.bind(this); if this.submit is never passed to a component event handler like onClick)
  • All JSX used for rendering exists in the render method
  • The component has the minimum amount of code necessary for its purpose, and it is broken down into smaller components in order to separate concerns and functions
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG)
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• For any bug fix or new feature in this PR, I verified that sufficient unit tests are included to prevent regressions in this flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.
• I have checked off every checkbox in the PR reviewer checklist, including those that don't apply to this PR.

Screenshots/Videos

Android: HybridApp

android.mov

Android: mWeb Chrome

mchrome.mov

iOS: HybridApp

ios.mov

iOS: mWeb Safari

ios.mov

MacOS: Chrome / Safari

msafari.mov

[aimane-chnaif]

Performance comparison:

comparison.mov

[mountiny]

Thanks!

[OSBotify]

✋ This PR was not deployed to staging yet because QA is ongoing. It will be automatically deployed to staging after the next production release.

[OSBotify]

🚀 Deployed to staging by https://github.com/mountiny in version: 9.2.42-0 🚀

platform	result
🖥 desktop 🖥	success ✅
🕸 web 🕸	success ✅
🤖 android 🤖	success ✅
🍎 iOS 🍎	success ✅

[OSBotify]

🚀 Deployed to production by https://github.com/luacmartins in version: 9.2.42-11 🚀

platform	result
🖥 desktop 🖥	success ✅
🕸 web 🕸	success ✅
🤖 android 🤖	success ✅
🍎 iOS 🍎	success ✅