The community bulletin board has 2 sections that can be used by Wikipedians for announcements: "Events and projects" and "WikiProject notices". In general, keep it concise (under 2 lines), refrain from fancy formatting, and new entries should be placed at the top of their section.
Events and projects: In this section, only organized events, projects, and/or competitions should be listed. These are organized by how often they occur:
The Yearly section is for uncommon events, like events that only occur every year, once, or irregularly. The Monthly section is for events that occur each month, or are always ongoing.
WikiProject notices: In this section, any announcement, request for help or other notice from a WikiProject should be listed here.
Entries should be signed, and ordered from newest to oldest.
Entries are to be removed after a period of 6 months.
Welcome to the community bulletin board, which is a page used for announcements from WikiProjects and other groups. Included here are coordinated efforts, events, projects, and other general announcements.
The Core Contest is a six-week contest focusing on improving Wikipedia's most important and most viewed articles. Cash prizes will be awarded. The next (eleventh) contest will place from April 15 to May 31 2023... Entries at Wikipedia:The Core Contest/Entries.
WikiProject Women in Green are hosting their fourth Good Article (GA) Editathon from June 1 to 30, 2023. Participants are invited to improve articles about women or women's works (e.g., books, films) and gain experience in the GA peer review process as either a nominator or reviewer. Both new and experienced editors are welcome – resources and one-on-one support will be provided. Participants are eligible for a barnstar at the end of the event.
Monthly or continuous events
Monthly contest, WikiProject Military history. The contest department of the Military history WikiProject aims to motivate increased quality in military history articles by offering a form of friendly competition for project members making improvements to them. The primary contest available is a simple rolling competition that awards points for improving articles. The contest runs from the first to last day of each month.
The 100,000 Challenge. The quest to bring about 100,000 article improvements and creations globally through a series of 50,000/10,000/1000 Challenges for different regions and countries. This is a loose challenge, a list will not be maintained here, but the components will function independently on each of the subpages. Will be updated every week or two.
The 50,000 Destubbing Challenge is a long term challenge to destub 50,000 articles on English Wikipedia for every country and topic. It may take decades to accomplish, it may take ten years, it all depends on how many people actively contribute.
WikiProject Skiing and Snowboarding is currently being revived from inactive status and is looking for interested participants to join. Many articles under the project scope are in need of improvement/updates, and assessment needs to be worked on. The project is also currently being restructured, so any input is welcome! VarietyEditor (talk) 01:30, 16 January 2023 (UTC)Reply[reply]
The LoginNotify extension was not sending notifications since January. It has now been fixed, so going forward, you may see notifications for failed login attempts, and successful login attempts from a new device. 
Changes later this week
The new version of MediaWiki will be on test wikis and MediaWiki.org from 5 September. It will be on non-Wikipedia wikis and some Wikipedias from 6 September. It will be on all wikis from 7 September (calendar).
Starting on Wednesday, a new set of Wikipedias will get "Add a link" (Eastern Mari Wikipedia, Maori Wikipedia, Minangkabau Wikipedia, Macedonian Wikipedia, Malayalam Wikipedia, Mongolian Wikipedia, Marathi Wikipedia, Western Mari Wikipedia, Malay Wikipedia, Maltese Wikipedia, Mirandese Wikipedia, Erzya Wikipedia, Mazanderani Wikipedia, Nāhuatl Wikipedia, Neapolitan Wikipedia, Low German Wikipedia, Low Saxon Wikipedia, Nepali Wikipedia, Newari Wikipedia, Norwegian Nynorsk Wikipedia, Novial Wikipedia, N'Ko Wikipedia, Nouormand Wikipedia, Northern Sotho Wikipedia, Navajo Wikipedia, Nyanja Wikipedia, Occitan Wikipedia, Livvi-Karelian Wikipedia, Oromo Wikipedia, Oriya Wikipedia, Ossetic Wikipedia, Punjabi Wikipedia, Pangasinan Wikipedia, Pampanga Wikipedia, Papiamento Wikipedia, Picard Wikipedia, Pennsylvania German Wikipedia, Palatine German Wikipedia, Norfuk / Pitkern Wikipedia, Piedmontese Wikipedia, Western Punjabi Wikipedia, Pontic Wikipedia, Pashto Wikipedia). This is part of the progressive deployment of this tool to more Wikipedias. The communities can configure how this feature works locally. 
There is a way to have Wikipedia loaded on your computer so that you can view it when you don't have access to the Internet. It's called XOWA, and it's compatible with Microsoft Windows, OSX, Linux and Android.
XOWA allows users to download and import their own copy of Wikipedia using official database dumps, or by special hosted database files specifically created for use within XOWA. The application is designed to accurately display Wikipedia content through its own built-in browser, or by an internal hosted web server which allows users to access content using a browser of their own choice.
XOWA can load and display multiple wikis. It is not limited to just Wikipedia.