To many lines are breaking line numbers, editor and line highlighting

So i have an application where my customer needs support for large files.
Now we really are nearly finished with the project and now tested some files with some million lines.

But we recognized that first the line number area get’s weird white line seperators every fourth line after like 800.000 lines before it appears normally.

But the bigger problem is that from like line 1.597.830 on the editor actually goes further but the scroll is at it’s end so the cursor just movec out of sigth.

Also line highlighting get’s messed up at some point and left overs of the highlighted line stay visible.

Is there anything to do to avoid these behaviors atleast for some bigger files. Like obviously there is a limit somewhere… but i think it should be able to get a bit furthar than this, like in other text editors even files with 30 million lines are opened correctly.

CSS positioning falls apart at that point because it uses fixed-precision number internally. Version 6 has some mitigation for this, but version 5 doesn’t.