[Bug] Mouse drag-text selection failure when window is On-Top

[Douglaslzd]

Environment

• OS: Windows 11 Version 25H2
• AltSnap Version: v1.67

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Description

After using AltSnap to set a window to "Always-on-Top" (Pin), a specific text-selection bug occurs in certain applications. In Microsoft Word (Microsoft 365 MSO) and the modern Windows 11 Notepad, you can no longer click and drag the mouse cursor to highlight/select text. (But highlighting text via Shift + Arrow keys still works normally.)

• Affected Applications: MS Word ( Version 2605 Build 16.0.20026.20168 64-bit), Win11 Notepad (Modern XAML-based version).
• Unaffected Applications: Web Browsers (Chrome/Edge), PowerPoint, Windows 11 File Explorer (Drag-selection works fine here even when pinned).

Thank you for taking the time to look into these issues. Your work on maintaining AltSnap is highly appreciated!

[RamonUnch]

Plaese create separated Issues, this is very annoying to have things mixed like that, also your Issue 2 seems related to #745

[Douglaslzd]

Plaese create separated Issues, this is very annoying to have things mixed like that, also your Issue 2 seems related to #745

Sincerely sorry for the confusion and trouble caused by mixing these topics! 🙏I have submitted the first topic as a separate issue here: #747.
Issue2 is indeed related to #745. I only wanted to provide a more detailed version to help, but I'd be happy to close this if it's redundant. Should I close it?

Apologies again for the inconvenience!

[RamonUnch]

Thanks for separating in two Issues.

Did you try to:

1. Disable the topmost Indicator (Advanced Tab, Last Option at the bottom).
2. See if there are other window Pinners that have the same Issue. I think there is even one in PowerToys.

AltSnap Only sets the TOPMOST flag to the parent-most windows attributes, Some programs maybe just don't like it.

EDIT: Obviously I will try to test myself as well.

[Douglaslzd]

1. Disable the topmost Indicator (Advanced Tab, Last Option at the bottom).

2. See if there are other window Pinners that have the same Issue. I think there is even one in PowerToys.

Awesome! Disabling the topmost indicator actually worked! (For both v1.65 and v1.67)

Also, this issue doesn't seem to occur in PowerToys v0.100.0.

[RamonUnch]

I guess it is the way the indicator works...
On my PC I was not able to reproduce the Issue, even with the Indicator enabled,

Maybe your Input Management Engine (IME) is giving this issue when combined with the topmost indicator?

[Douglaslzd]

It’s a bit unfortunate that it can't be reproduced on your PC.
For the IME, I'm just using the built-in Microsoft IME on Windows 11 (no third-party ones). I'm not entirely sure if it's the root cause. Anyway, the impact is quite minor so I can just work around it for now.

If I notice any new patterns or figure out the cause later, I’ll be sure to update you here. Appreciate your help!

[18878561964]

It's interesting that I installed version 1.67 on my friend and found that it can slide and select normally. And mine is also version 1.67, but it cannot slide. But he reproduced the problem of the old version: after canceling the top (I don't know if it's related to this, it doesn't seem like it's because of the cancellation issue), the window cannot slide. When Win+d returns to the desktop, the window follows the mouse movement and the right-click changes to maximize/minimize. I'm sure it's all version 1.67, we're both running on Windows 11 system. Summary: My friend did not encounter any issues with the new version (1.67), but encountered issues with the old version (which I had encountered before).
Addendum: I went to my friend's place to download and install it, in order to use it more in line with my operation. After the problem occurred, I had to exit the program at his place to restore normalcy.

我猜这是指示器的工作方式......在我的电脑上，即使启用了指示器，我也无法重现这个问题，

也许你的输入管理引擎（IM）在和最顶指示器结合时出现了这个问题？

[RamonUnch]

This weird, there should be no changes for the topmost indicator between those versions. But this maybe explains why I was unable to reproduce.

Maybe there are other third parties programs that might interact in some cases, and that is why the bug is not reproducible?