DigitalVolcano Software Support

I just realized this might not be a bug as "Generate preview for all matches" when checked is properly showing 123123123123 as it's reading the change from 123 -> 123123 (and \1\1 from that regex applied to 123123 -> 123123123123).

Build 4.0.0.1 BETA

Steps to reproduce:
1) Create a text file, "test.txt", with the following content:
The quick brown fox jumped over the 123 lazy dogs.

2) Under Settings > Regular Expression engine:
Engine: PCRE2

3) Under Find & Replace > Regular Expression:

Reg Ex: ([0-9]+)
Replace: \1\1 ...