Perf: getTransactionsSections optimization

[OlimpiaZurek]

Explanation of Change

Problem

Switching between bottom tabs on native devices is sluggish and the performance degrades significantly for users with large amounts of data. Profiling revealed that getTransactionsSections() is a key bottleneck, repeatedly invoking expensive functions like getActions() and getTransactionItemCommonFormattedProperties()` within tight loops

We identified several performance bottlenecks across the following functions:

• getTransactionsSections - repeated checks, unnecessary intermediate arrays (.filter().map()), and object spreading ({...transactionItem}) on each iteration.
• getActions- repeated inline logic for fetching reports, permissions, and violations; unnecessary filtering of transactions.
• getTransactionItemCommonFormattedProperties - redundant calls to getDisplayNameOrDefault() and eager formatting/fallbacks.

Solution

To improve performance, the following optimizations were implemented:

• getTransactionsSections -replaced .filter().map() with a for...of loop, moved static values outside the loop, and replaced the spread operator with direct property assignment.
• getActions - split logic into helper functions and deferred expensive operations until necessary.
• getTransactionItemCommonFormattedProperties - reused display names, applied lazy fallbacks, and reduced unnecessary formatting.

Performance gain : For ~100 transactions, optimizations reduced processing time from about 30–40 ms down to 18–25 ms, a roughly 39% improvement.

Fixed Issues

$ #60007
PROPOSAL:

Tests

• Verify that no errors appear in the JS console

Offline tests

QA Steps

// 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
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Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

MacOS: Desktop