The scrollbar in full-screen chat mode cannot scroll to the bottom.

[guoiaoang]

Steps to reproduce

When I tried to repeatedly press the home button to load the history messages and then drag the scroll bar to view the messages below, the scroll bar disappeared while I was still holding down the mouse button, and then I couldn't scroll to the bottom.When submitting this bug report, it was found that the scrollbar seemed to disappear when it reached a certain threshold.

I tried several translations but lost some information, so I've included the original text below:
当我尝试反复按 Home 键加载历史消息，然后拖动滚动条查看下方消息时，滚动条在我还按住鼠标按钮时就消失了，导致我无法滚动滚动条到最底部（消息可以正常滚动）。同时提交这个 bug 时测试发现，滚动条似乎在达到某个阈值后就会消失。

Expected behaviour

The scroll bar scrolls to the bottom, aligning with the message position.

Actual behaviour

The chat messages have scrolled to the bottom, but the scroll bar hasn't. Furthermore, the scroll bar disappears when scrolling down to a certain position or beyond.

Figure 1: The message history has scrolled to the bottom, but the scroll bar is not at the bottom.

Figure 2: The scroll bar is still displayed at this position.

Figure 3: It only scrolled a little more than in Figure 2, and then the scroll bar slider disappeared.

Operating system

Windows 11

Version of Telegram Desktop

7.0.9

Installation source

Downloaded from desktop.telegram.org or GitHub

Crash ID

No response

Logs

[Aokromes]

if you scroll a lot server slows you for a time and you need to wait.

[guoiaoang]

This situation can be reproduced by scrolling up less than 30 times, and these messages seem to have been fetched locally, as they are still present even after multiple scrolls.

[guoiaoang]

When the slider disappears at the bottom, the test shows that the scroll bar can be clicked, but the message history is scrolled upwards, which is inconsistent with the design of the scroll bar.