ArticlesRetirement: Project Task Gantt and Classic Gantt

Why are Project Task Gantt and Classic Gantt being retired?

• Project Task Gantt and Classic Gantt, both built using Sencha/EXTJS, are being retired primarily because Certinia is no longer developing within this framework
• Sencha development results in worse performance at scale compared to Lightning, and offers a less desirable customer UX than Lightning
• Additionally, Bryntum, a key component provider for Sencha, will no longer support it after December 2026, creating further risks
• The replacement, Project Gantt, offers a modern Lightning-based experience with better performance and user interface

What is the impact of this replacement on users?

• Customers will need to transition their processes and potentially update configurations to utilize the Project Gantt
• Certinia recognizes the scale of this impact and is planning a multi-year transition process to minimize disruption

What is replacing Project Task Gantt and Classic Gantt?

• Both Project Task Gantt and Classic Gantt are being replaced by the Project Gantt on a Project Record page
• The Project Gantt is a Lightning-based component designed to offer improved performance, better user experience, and continued feature development

What is the timeline for the replacement of Project Task Gantt and Classic Gantt?

• The replacement for both Project Task Gantt and Classic Gantt has been announced with the Spring 2026 release
• The features will have replacement notices added to them in subsequent releases
• They are slated to be completely removed from the product package by the Spring 2027 release
• This multi-release timeline aims to provide customers with sufficient time to transition to the Project Gantt

How should existing users transition to Project Gantt?

• Existing users can begin using the Project Gantt in parallel with the Project Task Gantt and Classic Gantt by assigning users the appropriate permission set (PSA - edit Project Gantt)
• To fully transition, users must remove permissions from the old Gantts and grant permissions for the Project Gantt components
• The same packaged field set that has been used for Classic Gantt can also be used for Project Gantt
  • Just custom setting-driven behaviors may require administrators to update LAB options in the Project Gantt
• Users may need to create new app pages for the Project Gantt and restrict permissions accordingly

What does Project Gantt offer that Classic Gantt and Project Task Gantt don't (as of Summer 2026)?

Project Gantt covers almost everything the older Gantts do and adds capabilities they never had:

• Impact Analysis Panel: see which resources become over-allocated, by how many hours and on which tasks, before you save a change
• Project Task Commenting: threaded comments on the Gantt and the Project Task Board
• Resource overallocation display: a warning icon on affected rows and red frames in the timeline showing when the overallocation happens
• Baseline comparison: compare the current schedule against a saved baseline
• Predecessor/Successor columns: set dependencies by typing them into the task grid
• Time editing: edit a task's start and end time of day in the Gantt
• Assignment Details Panel: see assignment status, milestone, dates and hours in Manage Resources
• Cell replication of assigned resources: drag to fill resources across many tasks at once
• Shareable saved filters: save filters as private or public
• Export to XLSX: export Gantt data to Excel

Built on Lightning, it performs better at scale and keeps receiving new features every release.

What Project Gantt capability can I expect, based on which release I'm on?

Each release adds to the previous ones: you have everything listed for your release and the releases before it. Features marked [New] are not available in Classic Gantt or Project Task Gantt.

Previous releases (before Winter 2026)

• Details Panel for Task, Resources and Milestone.
• [New] Baseline comparison.
• Saved filters, [New] shareable as private or public.
• [New] Resource overallocation display: warning icon and red timeline frames.
• [New] Predecessor/Successor columns for setting dependencies.
• Adding, updating and deleting resources assigned to project tasks.

Winter 2026 release

• Improved printing.
• Synchronization of milestone target dates with task end dates.
• Allocation modes and a Details Panel in the Manage Resources modal.

Spring 2026 release

• Dependency lag.
• Estimated Time to Completion (ETC) editing and roll-up.
• Milestone/task synchronization validation: a milestone can no longer be linked to multiple tasks.
• External resources in Manage Resources.
• [New] Impact Analysis Panel.
• [New] Export Gantt data as XLSX.

Summer 2026 release

• [New] Time editing: Start Date & Time and End Date & Time columns.
• Collapsed task groups are remembered.
• Task dates shift when the project start date changes.
• [New] Assignment Details Panel in Manage Resources.
• Estimated cost calculated per row and rolled up to parent tasks.
• Global Gantt Settings for Manage Resources, such as equal-split allocation.
• Editable Percent Complete, with parent tasks auto-completing.
• Large saves submitted in batches to stay within governor limits.
• Reload on save, configurable in the Preferences panel.
• Cell replication by corner drag, [New] including assigned resources. This covers Classic Gantt's bulk resource assignment and copy-paste.
• The Gantt works in the project's time zone.
• Dependencies reschedule tasks forwards and backwards; parent tasks move with their children.
• Cost and Hours formula fields recalculate live.
• [New] Project Task Commenting on the Gantt and the Project Task Board.

What specific features from Project Task Gantt and/or Classic Gantt will not be available in Project Gantt?

• The scheduler view.
  • Alternative: place the Work Planner alongside the Project Gantt on the Project record page for visibility into assignments and resource requests.
• Creating or deleting milestones directly in the Gantt. Milestones can be created with a Lightning action.
• The Edit Dependencies modal opened by double-clicking a dependency arrow.
  • Set the dependency type and lag in the Predecessor/Successor columns instead.
  • To delete a dependency, click the arrow and then the X icon.

Which features from Project Task Gantt and/or Classic Gantt are not yet available in Project Gantt?

• Preference settings for Adjust This Project's End Date (available on the project details) and Enable Keyboard Shortcuts.
• Comparing time zones on a second timeline. This is largely covered by the Gantt now working in the project's time zone.
• Front-end calculation and roll-up of Points fields. The Points fields themselves are available and editable.
• A "Held on this Project" filter in Manage Resources.
• Greater-than, less-than and between operators for numeric filters. Project Gantt supports equals only.

Read-only field sets and the hours zoom level are no longer needed: field-level security and sharing control editability, and time-of-day editing replaces the hours zoom.