Scrollback position constantly moves after clicking an old search result, disruping the ability to read anything

### Description

While browsing old messages, the scroll position jumps every time a new message arrives. This is aggravating on an active channel, as what I'm trying to read is continually yanked out of view every couple of seconds and I am left disoriented in some other part of the timeline.

### Steps to reproduce

- Scroll back in the message history
- Try to read old messages
- Notice that the text you're trying to read jumps out of position whenever a new message arrives

New messages should not cause on-screen text to move unless the message view is scrolled to the bottom.

Logs being sent: no

### Version information

- **Platform**: desktop?
- **OS**: Ubuntu
- **Version**: 1.7.5