Strategy Tester visual mode – Auto Scroll while paused

[ammer.jens]

Hi,

I had a longer break from coding and just came back to work on my EA and review my strategy again.

While using the Strategy Tester in visual mode, I noticed something that feels different from how I remember it.

When the test is running, I have Auto Scroll enabled and the chart follows the current price as expected.

But when I press Pause and try to scroll back to inspect older candles, the chart keeps jumping back to the current/latest candle.

I remember that before, I could simply pause the test and then scroll freely to the left. Auto Scroll would still work normally again when I resumed the test.

Turning Auto Scroll off manually is not really the same, because then the chart also stops following the price while the test is running.

So I am not sure if I remember this wrong, if something changed in a newer MT5 version, or if this is a bug.

Does anyone else see the same behavior in the current version?

I am using MetaTrader 5, build 6230, dated 25 September 2026.

[ammer.jens]

ammer.jens:

Hi,

I had a longer break from coding and just came back to work on my EA and review my strategy again.

While using the Strategy Tester in visual mode, I noticed something that feels different from how I remember it.

When the test is running, I have Auto Scroll enabled and the chart follows the current price as expected.

But when I press Pause and try to scroll back to inspect older candles, the chart keeps jumping back to the current/latest candle.

I remember that before, I could simply pause the test and then scroll freely to the left. Auto Scroll would still work normally again when I resumed the test.

Turning Auto Scroll off manually is not really the same, because then the chart also stops following the price while the test is running.

So I am not sure if I remember this wrong, if something changed in a newer MT5 version, or if this is a bug.

Does anyone else see the same behavior in the current version?

I am using MetaTrader 5, build 6230, dated 25 September 2026.

Small update:

I just noticed something else which might be related.

When the visual test is paused and Auto Scroll is enabled, mouse input seems to advance the backtest.

For example:

• If I click somewhere in the chart, the test moves forward by one tick.
• If I use the mouse wheel and scroll up, it also moves forward tick by tick.
• If I scroll the other way to move back in the chart, Auto Scroll immediately pushes the chart back to the latest position.

So even while the tester is paused, normal mouse actions seem to trigger some kind of update/next tick.

I am pretty sure this did not happen before. When paused, the chart should stay completely frozen and I should be able to inspect older candles without the simulation moving forward.

Can someone with the current build please check if they see the same behavior?

[Alain Verleyen]

Behaviour not reproducible. 

Try to record a video if possible.

[Atbin Sorahitalab]

Alain Verleyen #:

Behaviour not reproducible. 

Try to record a video if possible.

Here you go. I have the same problem. You can see when I press the mouse button, the tester keeps going...

[Alain Verleyen]

Atbin Sorahitalab #:

Here you go. I have the same problem. You can see when I press the mouse button, the tester keeps going...

Yes I see it but I can't reproduce that behaviour. Without reproducing it's very hard to fix.

Please provide the Journal log (from the Visual Tester).

Can you try a visual test with only a standard EA (Moving Average for example), to check if you get the same behaviour ?

[Atbin Sorahitalab]

I think I know what is causing the problem;

when an EA handles Chart Events - meaning it has following function, the problem appears. Otherwise, the chart stays put. 

void OnChartEvent(const int id,
                  const long &lparam,
                  const double &dparam,
                  const string &sparam)
  {

  }

 I added this piece to multiple EAs and the result confirmed my assumption.

[ammer.jens]

Hi everyone,

First, sorry for my late reply, and many thanks to @Atbin for the video and for finding the cause of the problem!

I just tested it myself and can confirm exactly the same behavior.

I tested it with a standard EA and also with my own EA, which has more than 100,000 lines of code.

Without the OnChartEvent function, everything works normally again. When I pause the visual tester, I can scroll back to older candles, and mouse clicks and keyboard inputs don't move the tester forward.

But as soon as I add the OnChartEvent function, the problem comes back. Even if the function body is completely empty, or all code inside is commented out, every mouse click or keyboard input moves the paused tester forward by one tick. Scrolling back also doesn't work anymore because the chart jumps back to the latest candle.

So I can confirm that just having the OnChartEvent function in the EA is enough to cause this problem.

Thanks again, Atbin! Hopefully this helps to fix the bug.

[Alain Verleyen]

I confirm the issue and reported it to MetaQuotes. Thank you.

[ammer.jens]

Thank you, Alain, for reporting it! 

[Atbin Sorahitalab]

Alain Verleyen #:
I confirm the issue and reported it to MetaQuotes. Thank you.

I appreciate it; thanks.

[Alain Verleyen]

Fixed from build 6286.