1721977 - [XFA] Filling into a very long form PDF will eventually cause the browser to feel sluggish

Status: VERIFIED FIXED

(Firefox :: PDF Viewer, defect, P1)

Description

[Daniel Bodea [:danibodea]]

Attachment: SuperSCIA-Campania-editabile-1.0-2.pdf

Note

• When the user loads a very long PDF file and inputs text into every field, he will notice that at some point it will start to feel sluggish.

Affected versions

• Nightly v92.0a1

Affected platforms

• all

Preconditions

• Flip the "pdfjs.enableXfa" pref to true.

Steps to reproduce

1. Launch browser.
2. Load the attached PDF file.
3. Input text into every field.

Expected result

• The performance does not change from the start to the end of filling it.

Actual result

• When reaching the last few pages, the PFD started to feel sluggish; It did not make it unusable, but definitely uncomfortable as letters typed did not appear as soon as pushed.

Regression range

• I does not appear to be a regression.

Additional information:

• I have captured a performance profile:
  https://share.firefox.dev/3eJK02c
• I hope it helps, additionally let me know if a memory profile would be better.

Comment 1

[GitHub Bugzilla PR Linker]

Attachment: Link to GitHub pull-request: https://github.com/mozilla/pdf.js/pull/13782

Comment 2

[GitHub Bugzilla PR Linker]

Attachment: Link to GitHub master push: https://github.com/mozilla/pdf.js/commit/834a638aad900f511836851c5b148ed6f58b2a7d

Commit merged into master by GitHub
Authored by Jonas Jenwald (Snuffleupagus)

Comment 3

[Daniel Bodea [:danibodea]]

I can confirm the fix on Nightly v92.0a1 from 2021-08-02 and Beta v91.0b9.