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Regex expression to get numbers without parentheses ()

I'm trying to create a regex that will select the numbers/numbers with commas(if easier, can trim commas later) that do not have a parentheses after and not the numbers inside the parentheses should not be selected either.
Used with the JavaScript's String.match method
Example strings
9(296,178),5,3(123),10
10,9(296,178),2,5,3(123),3(124,125)
10,7,5(296,293,444,1255),3(218),2,4
What i have so far:
/((^\d+[^\(])|(,\d+,)|(,*\d+$))/gm
I tried this in regex101 and underlined the numbers i would like to match and x on the one that should not.

You could start with a substitution to remove all the unwanted parts:
/\d*\(.*?\),?//gm
Demo
This leaves you with
5,10
10,2,5,
10,7,2,4
which makes the matching pretty straight forward:
/(\d+)/gm
If you want it as a single match expression you could use a negative lookbehind:
/(?<!\([\d,]*)(\d+)(?:,|$)/gm
Demo - and here's the same matching expression as a runnable javascript (skeleton code borrowed from Wiktor's answer):
const text = `9(296,178),5,3(123),10
10,9(296,178),2,5,3(123),3(124,125)
10,7,5(296,293,444,1255),3(218),2,4`;
const matches = Array.from(text.matchAll(/(?<!\([\d,]*)(\d+)(?:,|$)/gm), x=>x[1])
console.log(matches);

Here, I'd recommend the so-called "best regex trick ever": just match what you do not need (negative contexts) and then match and capture what you need, and grab the captured items only.
If you want to match integer numbers that are not matched with \d+\([^()]*\) pattern (a number followed with a parenthetical substring), you can match this pattern or match and capture the \d+, one or more digit matching pattern, and then simply grab Group 1 values from matches:
const text = `9(296,178),5,3(123),10
10,9(296,178),2,5,3(123),3(124,125)
10,7,5(296,293,444,1255),3(218),2,4`;
const matches = Array.from(text.matchAll(/\d+\([^()]*\)|(\d+)/g), x=> x[1] ?? "").filter(Boolean)
console.log(matches);
Details:
text.matchAll(/\d+\([^()]*\)|(\d+)/g) - matches one or more digits (\d+) + ( (with \() + any zero or more chars other than ( and ) (with [^()]*) + \) (see \)), or (|) one or more digits captured into Group 1 ((\d+))
Array.from(..., x=> x[1] ?? "") - gets Group 1 value, or, if not assigned, just adds an empty string
.filter(Boolean) - removes empty strings.

Using several replacement regexes
var textA = `9(296,178),5,3(123),10
10,9(296,178),2,5,3(123),3(124,125)
10,7,5(296,293,444,1255),3(218),2,4
`
console.log('A', textA)
var textB = textA.replace(/\(.*?\),?/g, ';')
console.log('B', textB)
var textC = textB.replace(/^\d+|\d+$|\d*;\d*/gm, '')
console.log('C', textC)
var textD = textC.replace(/,+/g, ' ').trim(',')
console.log('D', textD)
With a loop
Here is a solution which splits the lines on comma and loops over the pieces:
var inside = false;
var result = [];
`9(296,178),5,3(123),10
10,9(296,178),2,5,3(123),3(124,125)
10,7,5(296,293,444,1255),3(218),2,4
`.split("\n").map(line => {
let pieceArray = line.split(",")
pieceArray.forEach((piece, k) => {
if (piece.includes('(')) {
inside = true
} else if (piece.includes(')')) {
inside = false
} else if (!inside && k > 0 && k < pieceArray.length-1 && !pieceArray[k-1].includes(')')) {
result.push(piece)
}
})
})
console.log(result)
It does print the expected result: ["5", "7"]

Regex to get substring between first and last occurence

Assume there is the string
just/the/path/to/file.txt
I need to get the part between the first and the last slash: the/path/to
I came up with this regex: /^(.*?).([^\/]*)$/, but this gives me everything in front of the last slash.

Don't use [^/]*, since that won't match anything that contains a slash. Just use .* to match anything:
/(.*?)\/(.*)\/(.*)/
Group 1 = just, Group 2 = the/path/to and Group 3 = file.txt.

The regex should be \/(.*)\/. You can check my below demo:
const regex = /\/(.*)\//;
const str = `just/the/path/to/file.txt`;
let m;
if ((m = regex.exec(str)) !== null) {
console.log(m[1]);
}

This regex expression will do the trick
const str = "/the/path/to/the/peace";
console.log(str.replace(/[^\/]*\/(.*)\/[^\/]*/, "$1"));
[^\/]*\/(.*)\/[^\/]*

If you are interested in only matching consecutive parts with a single / and no //
^[^/]*\/((?:[^\/]+\/)*[^\/]+)\/[^\/]*$
^ Start of string
[^/]*\/ Negated character class, optionally match any char except / and then match the first /
( Capture group 1
(?:[^\/]+\/)* Optionally repeat matching 1+ times any char except / followed by matching the /
[^\/]+ Match 1+ times any char except /
) Close group 1
\/[^\/]* Match the last / followed by optionally matching any char except /
$ End of string
Regex demo
const regex = /^[^/]*\/((?:[^\/]+\/)*[^\/]+)\/[^\/]*$/;
[
"just/the/path/to/file.txt",
"just/the/path",
"/just/",
"just/the/path/to/",
"just/the//path/test",
"just//",
].forEach(str => {
const m = str.match(regex);
if (m) {
console.log(m[1])
};
});

js Remove a part from a parameter which doesnt fit a pattern

const regex = /[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}/gm;
let m;
while ((m = regex.exec(tweet.text)) !== null) {
let newClass = tweet.text.replace(/[^1-9a-zA-Z]{3}-[^1-9a-zA-Z]{3}-[^1-9a-zA-Z]{3}/g, '');
console.log(`Found match: ${newClass}`);
};
when tweet.text = "123.qwe.456 test" I still get the same output but I want to remove anything which doesnt fit the pattern
/[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}/
any ideas?

You can use capture groups to extract exactly what gets matched in your string and then replace your original variable with this value. Something like
const regex = /([1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3})/
let match = tweet.text.match(regex)
tweet.text = match[1]

Instead of replace, you can get the match instead
\b[1-9a-zA-Z]{3}([-.])[1-9a-zA-Z]{3}\1[1-9a-zA-Z]{3}\b
Explanation
\b A word boundary
[1-9a-zA-Z]{3} Match 3 times any of the listed (Note that 1-9 does not match a 0)
([-.]) Capture in group 1 either an - or .
[1-9a-zA-Z]{3} Match 3 times any of the listed
\1 Back reference to group 1, match the same as captured in group 1
[1-9a-zA-Z]{3} Match 3 times any of the listed
\b A word boundary
Regex demo

const regex = /[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}-[1-9a-zA-Z]{3}/gm;
let m;
while ((m = regex.exec(tweet.text)) !== null) {
console.log(`Found match: ${m[0]}`);
figured the solution

regular expression replacement in JavaScript with some part remaining intact

I need to parse a string that comes like this:
-38419-indices-foo-7119-attributes-10073-bar
Where there are numbers followed by one or more words all joined by dashes. I need to get this:
[
0 => '38419-indices-foo',
1 => '7119-attributes',
2 => '10073-bar',
]
I had thought of attempting to replace only the dash before a number with a : and then using .split(':') - how would I do this? I don't want to replace the other dashes.

Imo, the pattern is straight-forward:
\d+\D+
To even get rid of the trailing -, you could go for
(\d+\D+)(?:-|$)
Or
\d+(?:(?!-\d|$).)+
You can see it here:
var myString = "-38419-indices-foo-7119-attributes-10073-bar";
var myRegexp = /(\d+\D+)(?:-|$)/g;
var result = [];
match = myRegexp.exec(myString);
while (match != null) {
// matched text: match[0]
// match start: match.index
// capturing group n: match[n]
result.push(match[1]);
match = myRegexp.exec(myString);
}
console.log(result);
// alternative 2
let alternative_results = myString.match(/\d+(?:(?!-\d|$).)+/g);
console.log(alternative_results);
Or a demo on regex101.com.

Logic
lazy matching using quantifier .*?
Regex
.*?((\d+)\D*)(?!-)
https://regex101.com/r/WeTzF0/1
Test string
-38419-indices-foo-7119-attributes-10073-bar-333333-dfdfdfdf-dfdfdfdf-dfdfdfdfdfdf-123232323-dfsdfsfsdfdf
Matches
Further steps
You need to split from the matches and insert into your desired array.

Javascript Regex: Capture between two asterisks with multiple asterisks in comma delimited string

I am trying to capture all characters between multiple instances of asterisks, which are comma delimited in a string. Here's an example of the string:
checkboxID0*,*checkboxID1*,&checkboxID2&,*checkboxID3*,!checkboxID4!,checkboxID5*
The caveat is that the phrase must start and end with an asterisk. I have been able to come close by using the following regex, however, it won't discard any matches when the captured string is missing the starting asterisk(*):
let str = "checkboxID0*,*checkboxID1*,&checkboxID2&,*checkboxID3*,!checkboxID4!,checkboxID5*"
const regex = /[^\,\*]+(?=\*)/gi;
var a = str.match(regex)
console.log(a) // answer should exclude checkboxID0 and checkboxID5
The answer returns the following, however, "checkboxID0 and checkboxID5" should be excluded as it doesn't start with an asterisk.
[
"checkboxID0",
"checkboxID1",
"checkboxID3",
"checkboxID5"
]
Thanks, in advance!

You need to use asterisks on both ends of the pattern and capture all 1 or more chars other than commas and asterisks in between:
/\*([^,*]+)\*/g
See the regex demo
Pattern details
\* - an asterisk
([^,*]+) - Capturing group 1: one or more chars other than , and *
\* - an asterisk
JS demo:
var regex = /\*([^,*]+)\*/g;
var str = "checkboxID0*,*checkboxID1*,&checkboxID2&,*checkboxID3*,!checkboxID4!,checkboxID5*";
var m, res = [];
while (m = regex.exec(str)) {
res.push(m[1]);
}
console.log(res);