'Tab' navigatin Bug. Ctrl+PageUp -> Next Tab, Ctrl+PageDown -> Previous Tab.

[parkjunhong]

Summary

In Eclipse IDE 2026-06 (4.40), the Ctrl+PageUp and Ctrl+PageDown keyboard shortcuts navigate editor tabs in the opposite direction compared to all previous versions.

This shortcut pair has been stable for many years (confirmed in 2026-03 / 4.39 and earlier):

Shortcut	Expected behaviour (≤ 2026-03)	Actual behaviour (2026-06)
Ctrl+PageUp	Previous Tab (← move left)	Next Tab (→ move right) ❌
Ctrl+PageDown	Next Tab (→ move right)	Previous Tab (← move left) ❌

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Steps to Reproduce

1. Install Eclipse IDE 2026-06 R (4.40) — any package (JEE, Java, etc.)
2. Open 3 or more source files in the editor area (e.g. A.java, B.java, C.java)
3. Click on A.java to make it the active editor
4. Press Ctrl+PageDown
   • Expected: moves to B.java (next tab — one step to the right)
   • Actual: moves to the tab on the left (previous tab direction)
5. Press Ctrl+PageUp
   • Expected: moves back to A.java (previous tab — one step to the left)
   • Actual: moves to the tab on the right (next tab direction)

The two shortcuts are completely swapped in direction.

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Expected Behaviour

• Ctrl+PageUp → moves to the previous (left) editor tab
• Ctrl+PageDown → moves to the next (right) editor tab

This is the documented and long-established behaviour:
https://help.eclipse.org/latest/topic/org.eclipse.platform.doc.user/concepts/accessibility/navigation.htm

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Actual Behaviour

• Ctrl+PageUp → moves to the next (right) editor tab ← reversed
• Ctrl+PageDown → moves to the previous (left) editor tab ← reversed

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Environment

Item	Value
Eclipse version	2026-06 R (4.40.0)
Package	Eclipse IDE for Enterprise Java and Web Developers (JEE)
Last working version	2026-03 R (4.39.0)
OS	Windows 10 / 11 (x86_64)
JVM	Eclipse-bundled JRE 21

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Additional Context

• This regression affects plain Java editors and is not limited to multi-page editors (e.g. Maven POM).
• The preference binding under Window → Preferences → General → Keys still shows Ctrl+PageUp mapped to Previous Editor and Ctrl+PageDown mapped to Next Editor, confirming the key-binding metadata is unchanged. The actual navigation direction of the underlying implementation appears to have been inverted.
• A related but narrower bug was previously reported for multi-page editors in 2025-03:
  → #2864 — Eclipse 2025-03 Next Tab navigation broken with POM XML editor
• Historical Bugzilla reference:
  → Bug 199499 — Switching tabs by Ctrl+PageUp/PageDown must not be caught on the inner tab set

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Workaround

Until a fix is available, the direction can be manually corrected under:

Window → Preferences → General → Keys

1. Search for Previous Editor → reassign to Ctrl+PageUp (overwrite if needed)
2. Search for Next Editor → reassign to Ctrl+PageDown (overwrite if needed)

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Suggested Fix Area

The regression is likely in the CTabFolder traversal logic within the SWT/Platform UI layer — specifically the handler that maps SWT.TRAVERSE_PAGE_NEXT / SWT.TRAVERSE_PAGE_PREVIOUS events to Ctrl+PageDown / Ctrl+PageUp. A direction flag may have been inadvertently inverted in a recent commit targeting the 4.40 cycle.

[iloveeclipse]

I can't reproduce, however I'm on Linux, and this could be something that depends on platform specific SWT implementation.

[HeikoKlare]

I cannot reproduce this either. I am on the platform reported to be affected (Windows 11 22631) but the behavior is the same for me on 4.39 (2026-03), 4.40 (2026-06) and 4.41 (development state 2026-09). I have even specifically downloaded an "Eclipse IDE for Enterprise Java and Web Developers (JEE)", created a project with three classes, opened them and navigated between them according to the issue description, but find everything working as expected.

20260625-0828-58.9854556.mp4

@parkjunhong can you verify again what may be relevant to reproduce the reported issue? Maybe you also share a video demonstrating the behavior? You can enable the visualization of used keys for a video, so that it's easier to understand what happens: