[REQUEST]: add check only non-working proxies and a regex pattern check in the target section of the proxy checker

[eqiuwnzeqx9uuat]

This feature request respects the following points:

• [X] This is a feature request, not a question or a configuration issue; Please visit our forum first to troubleshoot with volunteers, before creating a report. The links can be found here.
• [X] This issue is not already reported on GitHub (I've searched it).
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• [X] This report addresses only a single feature request; If you have multiple feature request, kindly create separate reports for each one.

Description of the feature request

in the proxy check section add check only non-working proxies instead of checking all proxies each time (even the working ones, which doesn't make sense) also it would be useful to have a regex pattern check in the target section

Is your feature request related to a problem

every time I have to check all proxies instead of being able to check only the broken proxies as it would be logical to do, also it is not possible to use regex in the target section when I check proxies

Describe the solution you'd like

No response

Describe alternatives you've considered

No response

Relevant screenshots or videos

No response

Additional information

No response

[openbullet]

Actually it does make sense to check working proxies when dealing with free proxies since they can go down at any time, so a proxy that was working might not be working anymore right now.