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+# On Matrix tombstones
+
+I am not putting the events here as I have [scripts for that separately](https://gitea.blesmrt.net/mikaela/scripts/src/branch/master/bash).
+
+## PL50 tombstoning
+
+Synapse versions before [1.11.0 (2020-02-21), technically 1.11.0rc1 (2020-02-19)](https://github.com/matrix-org/synapse/releases/tag/v1.11.0)
+allowed power level 50 to set tombstones and thus hijack rooms. Thus this is
+dependent on the Synapse version used at the time of room creation.
+
+* [PR](https://github.com/matrix-org/synapse/pull/6834)
+* [commit](https://github.com/matrix-org/synapse/commit/3404ad289b1d2e5bc5c7f277f519b9698dbdaa15)
+
+In the same context invites were changed to require PL50 by default, and ACL
+also got the requirement for PL100.