docs: Clarify supported formats for screenshots

- update list in the documentation to be complete
- remove incomplete list from the UI as any reasonable format should be
  supported

Fixes #9580

docs/admin/projects.rst

@@ -430,7 +430,7 @@ Screenshot file mask
 This feature allows the discovery and updating of screenshots through screenshot file masks, using paths from the VCS repository.
 This operates at the component level and necessitates the use of an asterisk "*" to replace the screenshot file name.
 
-Allowed formats are JPEG, PNG, APNG and GIF.
+Allowed formats are WebP, JPEG, PNG, APNG and GIF.
 
 Note:
 

weblate/screenshots/migrations/0007_alter_screenshot_image.py

@@ -0,0 +1,27 @@
+# Copyright © Michal Čihař <michal@weblate.org>
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+# Generated by Django 4.2.3 on 2023-07-17 08:01
+
+from django.db import migrations
+
+import weblate.screenshots.fields
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("screenshots", "0006_screenshot_repository_filename"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="screenshot",
+            name="image",
+            field=weblate.screenshots.fields.ScreenshotField(
+                help_text="Upload image up to 2000x2000 pixels.",
+                upload_to="screenshots/",
+                verbose_name="Image",
+            ),
+        ),
+    ]

weblate/screenshots/models.py

@@ -55,7 +55,7 @@ class Screenshot(models.Model, UserDisplayMixin):
     )
     image = ScreenshotField(
         verbose_name=gettext_lazy("Image"),
-        help_text=gettext_lazy("Upload JPEG or PNG images up to 2000x2000 pixels."),
+        help_text=gettext_lazy("Upload image up to 2000x2000 pixels."),
         upload_to="screenshots/",
     )
     translation = models.ForeignKey(Translation, on_delete=models.deletion.CASCADE)