searching or replacing with regex isn't working

### Operating System and Version

Win11

### Distribution

installer

### Description

Searching or replacing with regex isn't working - Here is what in the text file:

```
12-18 09:49:33.325 1120 1120 E audiohalservice: Failed to dlopen android.hardware.audio.sounddose-vendor-impl.so: dlopen failed: library "android.hardware.audio.sounddose-vendor-impl.so" not found
12-18 09:49:33.325 1120 1120 W audiohalservice: createISoundDoseFactory() from android.hardware.audio.sounddose-vendor-impl failed
12-18 21:42:09.309 0 0 I servicemanager: Caller(pid=1792,uid=1000,sid=u:r:system_server:s0) Could not find vendor.lineage.livedisplay.IAutoContrast/default in the VINTF manifest. No alternative instances declared in VINTF.
```

And here is the search string `^.*?(?=[IEVWDF]\s)` - this works on other similar notepad tools, but not on notepad next

### Steps to Reproduce

1. put the following in the text file"
```
12-18 09:49:33.325 1120 1120 E audiohalservice: Failed to dlopen android.hardware.audio.sounddose-vendor-impl.so: dlopen failed: library "android.hardware.audio.sounddose-vendor-impl.so" not found
12-18 09:49:33.325 1120 1120 W audiohalservice: createISoundDoseFactory() from android.hardware.audio.sounddose-vendor-impl failed
12-18 21:42:09.309 0 0 I servicemanager: Caller(pid=1792,uid=1000,sid=u:r:system_server:s0) Could not find vendor.lineage.livedisplay.IAutoContrast/default in the VINTF manifest. No alternative instances declared in VINTF.
```
2. hit ctrl+h and in the search string put `^.*?(?=[IEVWDF]\s)`
3. and select regular expression and hit find/replace - nothing gets replaced or nothing is found

### Debug Information

_No response_

### Additional Details

e.g. screenshots, logs, etc

Reproduce the issue in the Windows installer by opening the sample log, pressing Ctrl+H, enabling regular expressions, and using `^.*?(?=[IEVWDF]\s)`. Trace the search and replace entry point for regex mode; done means the expression finds and replaces the expected line prefixes rather than returning no results.

Written by the indexing model from the issue text.