diff --git a/www/firefox-esr/files/patch-toolkit_components_processtools_procinfo__bsd.c b/www/firefox-esr/files/patch-toolkit_components_processtools_procinfo__bsd.c
new file mode 100644
index 000000000000..e2e9a3cc88f4
--- /dev/null
+++ b/www/firefox-esr/files/patch-toolkit_components_processtools_procinfo__bsd.c
@@ -0,0 +1,104 @@
+diff --git toolkit/components/processtools/ProcInfo_bsd.cpp toolkit/components/processtools/ProcInfo_bsd.cpp
+index a6ff4881940c..f041ed5e50ce 100644
+--- toolkit/components/processtools/ProcInfo_bsd.cpp
++++ toolkit/components/processtools/ProcInfo_bsd.cpp
+@@ -18,6 +18,9 @@
+ #include <cstdio>
+ #include <cstring>
+ #include <unistd.h>
++#ifdef __FreeBSD__
++#include <sys/user.h>
++#endif
+ 
+ namespace mozilla {
+ 
+@@ -50,25 +53,39 @@ ProcInfoPromise::ResolveOrRejectValue GetProcInfoSync(
+   }
+   for (const auto& request : aRequests) {
+     size_t size;
++#ifdef __FreeBSD__
++    int mib[4];
++    int mibsize = 4;
++    mib[0] = CTL_KERN;
++    mib[1] = KERN_PROC;
++    mib[2] = KERN_PROC_PID | KERN_PROC_INC_THREAD;
++    mib[3] = request.pid;
++#else
+     int mib[6];
++    int mibsize = 6;
+     mib[0] = CTL_KERN;
+     mib[1] = KERN_PROC;
+     mib[2] = KERN_PROC_PID | KERN_PROC_SHOW_THREADS;
+     mib[3] = request.pid;
+     mib[4] = sizeof(kinfo_proc);
+     mib[5] = 0;
+-    if (sysctl(mib, 6, nullptr, &size, nullptr, 0) == -1) {
++#endif
++    if (sysctl(mib, mibsize, nullptr, &size, nullptr, 0) == -1) {
+       // Can't get info for this process. Skip it.
+       continue;
+     }
+ 
++#ifdef __FreeBSD__
++    auto procs = MakeUniqueFallible<kinfo_proc[]>(size / sizeof(kinfo_proc));
++#else
+     mib[5] = size / sizeof(kinfo_proc);
+     auto procs = MakeUniqueFallible<kinfo_proc[]>(mib[5]);
++#endif
+     if (!procs) {
+       result.SetReject(NS_ERROR_OUT_OF_MEMORY);
+       return result;
+     }
+-    if (sysctl(mib, 6, procs.get(), &size, nullptr, 0) == -1 &&
++    if (sysctl(mib, mibsize, procs.get(), &size, nullptr, 0) == -1 &&
+         errno != ENOMEM) {
+       continue;
+     }
+@@ -84,19 +101,34 @@ ProcInfoPromise::ResolveOrRejectValue GetProcInfoSync(
+     bool found = false;
+     for (size_t i = 0; i < size / sizeof(kinfo_proc); i++) {
+       const auto& p = procs[i];
++#ifdef __FreeBSD__
++      if (i == 0) {
++#else
+       if (p.p_tid == -1) {
++#endif
+         // This is the process.
+         found = true;
++#ifdef __FreeBSD__
++        info.cpuTime = uint64_t(p.ki_runtime) * 1'000u;
++        info.memory = (p.ki_tsize + p.ki_dsize + p.ki_ssize) * getpagesize();
++#else
+         info.cpuTime = uint64_t(p.p_rtime_sec) * 1'000'000'000u +
+                        uint64_t(p.p_rtime_usec) * 1'000u;
+         info.memory =
+             (p.p_vm_tsize + p.p_vm_dsize + p.p_vm_ssize) * getpagesize();
++#endif
++
+       } else {
+         // This is one of its threads.
+         ThreadInfo threadInfo;
++#ifdef __FreeBSD__
++        threadInfo.tid = p.ki_tid;
++        threadInfo.cpuTime = uint64_t(p.ki_runtime) * 1'000u;
++#else
+         threadInfo.tid = p.p_tid;
+         threadInfo.cpuTime = uint64_t(p.p_rtime_sec) * 1'000'000'000u +
+                              uint64_t(p.p_rtime_usec) * 1'000u;
++#endif
+         info.threads.AppendElement(threadInfo);
+       }
+     }
+diff --git toolkit/components/processtools/moz.build toolkit/components/processtools/moz.build
+index b7c164c1b0ac..a41dad52c343 100644
+--- toolkit/components/processtools/moz.build
++++ toolkit/components/processtools/moz.build
+@@ -39,7 +39,7 @@ BROWSER_CHROME_MANIFESTS += ["tests/browser/browser.ini"]
+ # Platform-specific implementations of `ProcInfo`.
+ toolkit = CONFIG["MOZ_WIDGET_TOOLKIT"]
+ if toolkit == "gtk" or toolkit == "android":
+-    if CONFIG["OS_TARGET"] == "OpenBSD":
++    if CONFIG["OS_TARGET"] == "FreeBSD" or CONFIG["OS_TARGET"] == "OpenBSD":
+         UNIFIED_SOURCES += ["ProcInfo_bsd.cpp"]
+     else:
+         UNIFIED_SOURCES += ["ProcInfo_linux.cpp"]