New yaml issue template (#7983)

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,79 @@
+name: "Bug report"
+description: Create a report to help us improve
+body:
+  - type: markdown
+    attributes:
+      value:
+        "Please use the GitHub issue tracker only for bug reports.
+        Feature requests, questions and general feedback is now handled at http://discourse.jabref.org.
+        Please make sure you looked into our [list of existing issues](https://github.com/jabref/JabRef/issues) before creating a new issue to avoid duplicates!"
+
+  - type: dropdown
+    attributes:
+      label: JabRef version
+      options:
+        - "5.3 (latest release)"
+        - "3.8.2"
+        - Latest development branch build (please note build date below)
+        - Other (please describe below)
+      description: The version as shown in the about dialog.
+    validations:
+      required: true
+
+  - type: dropdown
+    attributes:
+      label: Operating system
+      multiple: false
+      options:
+        - Windows
+        - GNU / Linux
+        - mac OS
+        - Other (please describe below)
+    validations:
+      required: true
+
+  - type: input
+    attributes:
+      label: Details on version and operating system
+      description: OS Version, distribution, desktop environment, older JabRef version etc.
+      placeholder: Ubuntu 21.04 with Plasma 5.22 / Windows 10 21H1 / Mac OS 10.14
+    validations:
+      required: false
+
+  - type: checkboxes
+    attributes:
+      label: Checked with the latest development build
+      description: |
+        Please always test if the bug is still reproducible in the latest development version. We are constantly improving JabRef and some bugs may already be fixed. If you already use a development version, ensure that you use the latest one.
+        You can download the latest development build at: https://builds.jabref.org/main/ . **Please make a backup of your library before you try out this version.**
+      options:
+        - label: I made a backup of my libraries before testing the latest development version.
+          required: true
+        - label: I have tested the latest development version and the problem persists
+          required: true
+
+  - type: textarea
+    attributes:
+      label: Steps to reproduce the behaviour
+      description: A clear and concise description of what the bug is and how to make it occur.
+      value: |
+        1. ...
+        2. ...
+        3. ...
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Appendix
+      description: "If applicable: An excerpt of the bibliography file, a screenshot, an excerpt of log (available in the error console) etc."
+      value: |
+        ...
+        <details>
+        <summary>Log File</summary>
+        ```
+        Paste an excerpt of your log file here
+        ```
+        </details>
+    validations:
+      required: false